AFT Australia introduced Flexi-dropper™, the first flexible sprinkler hose assembly into the Australian and New Zealand markets in 1998.

Advantages of using Flexi-dropper™ apply to the fire contractors, sprinkler fitters, builders, and building operators & owners.

Advantages for Fire Contractors

  • Reduces labour costs by increasing labour efficiency
  • Savings in equipment and operational costs
  • One-man operation
  • Reduction in requirement of testing and risk of water damage

The benefit of Installation for Fitters

  • Eliminates WHS hazards from the traditional installation process
  • Eliminates work inconvenience such as relocating machinery, drain down and recharging systems repeatedly

Advantages for Builders

  • Reduces manpower congestion during critical fit off stage
  • Reduction in risk of water damage during fit off
  • Short fit-out duration time required

Advantages for Builder Owner Operators

  • Long term preventative maintenance
  • Minimal disruption of business operation during tenancy and maintenance

Partner – Yong Won Inc, South Korea

Exclusive benefits:

  • 2 models – YB25 & YB28
  • Australian Standard AS2118.1:2017
  • 5 lengths (mm) – 700, 1000, 1200, 1500, 1800
  • Activfire/CSIRO, FM, and UL listings
  • Tailored packages – components and pricing
  • Wide range of component options to suit all ceiling configurations/limitations

Projects list:

Option 1

Using the standard Flexi-dropper arrangement with the straight 120mm reducer, in areas where the ceiling space is greater than 300mm

  • 1 x Braided Flexible Hose
  • 1 x Nipple
  • 1 x Straight Reducer 25mm x 10 or 15mm -120mm long

Ceiling Fixing Arrangement including:

  • 1 x Caring Bar 650mm long
  • 1 x OGRB Reducer Bracket
  • 2 x Ceiling Grid Clamps – 58mm long (for Semi-Recessed Heads) – 2 choices of clamp


Installation Option 1 setup


Option 2

Using the new Flexi-dropper arrangement with the small elbow reducer with the L shaped bracket attached to be fixed to the slab, in small ceiling spaces from approx 85 to 110mm.

  • 1 x Braided Flexible Hose
  • 1 x Nipple
  • 1 x small radius elbow Reducer 25mm x 15mm with L shaped bracket attached


Installation Option 2 Setup

This arrangement is not available in YB28 model


Option 3

Using Flexi-dropper arrangement with the small 90-degree elbow 25 x15 or 10mm -110mm long for ceiling spaces from approx 130 to 300mm.

  • 1 x Braided Flexible Hose
  • 1 x YB25 or YB28 Nipple
  • 1 x small elbow reducer 25mm x 10mm or 15mm -110mm long

Ceiling Fixing Arrangement including:

  • 1 x Caring Bar 650mm long
  • 1 x OGRB Reducer Bracket
  • 2 x Ceiling Grid Clamps – 38mm long (for Semi-Recessed Heads)


Installation Option 3 Setup


Option 4

Using Flexi-dropper arrangement with the 25mm nipple connected to one end of the flexible hose and a 25mm male/female connector on the other end of the hose. This is used as a connector between a range pipe & the external head over the balcony door.

  • 1 x Braided Flexible Hose
  • 1 x YB25 or YB28 Nipple
  • 1 x YB25 or YB28 M/F  connectors

Ceiling Fixing Arrangement including:

  • 1 x Caring Bar 650mm long
  • 1 x OGRB Reducer Bracket
  • 2 x Ceiling Grid Clamps – 58mm long (for Semi-Recessed Heads) – 2 choices of clamp


Installation Option 4 Setup


Balcony Penetration Options

Balcony Penetration Options


Extra Options

  • Caring bars:  1.3m | 1.6m
  • Clamps:  Aluminium Clamps in 58mm | Bronze Clamps in 58mm, 38mm and 90mm | 76mm Furring Channel Clamp


Place your Order Here:

Flexi Dropper Order Checklist


  • Reducers – 10mm, 15mm & 20mm
  • 10, 15 & 20mm Reducers available in both models at no additional cost, (no need to bush – bushing sets the reducer too high in the bracket and, as a result, it is not secured properly. There are also additional labour and material costs involved with bushing).
  • Bars 650mm, 1.3m & 1.6m
  • Available with standard 1.3m Bar for 1.2m x 0.6m Ceiling Grid, 650mm Bar for 0.6m x 0.6m Ceiling grid also available with 1.6m Bar for larger grid.
  • Elbows for Tight Spaces
  • Small elbow reducer with L shaped bracket for fixing to the slab to get into tight spaces of less than 100mm
  • Small Steel Elbow 90º available in 10mm or 15mm outlet x 90mm long fits in tight space (min 100mm) under ducts etc. The standard Ceiling Grid fixing arrangement can be used with the Small Elbow.
  • All Flexible Hose – up to 1.8m

Our flexi-dropper™ up to 1.8m inclusive use a fully flexible hose – other brands do not have fully flexible hose and have solid spacer in the length of tube, therefore, restricting flexibility; e.g. other brands’ 1.5m long flexi has 3 x 150mm long solid spacer tube in between the flexible hose.

  • Ceiling Grid Clamps – assembled and ready to go
  • Ceiling Grid Clamps come with phillips/hex head screws already screwed in where some other brands do not, resulting in additional labour putting in screws which are packed separately.
  • O Rings cannot slip out
  • Slip Nut has a mound underneath it to prevent it from sliding down the hose and exposing the O Ring inside slip nut which prevents the O Ring from coming out.
  • Reducers – several options in length & configuration

More options available in terms of additional components that can be substituted for standard assembly, e.g. 250mm long Reducers or Small 90º Elbow in lieu of straight 120mm long standard reducer.

Our technical specifications are available in PDF.
Click to view and download .


Approval summary

YB25 CSIRO Certificate of conformity afp1584 V21

YB28 CSIRO Certificate of conformity ATP 1249

UL Test – 200109

UL Certificate of Compliance

FM Approval report 27062006

FM Certificate of compliance

FM Certificate of Compliance Type A Elbow

Slide reducer bracket onto reducer.

  • Install inner escutcheon plate and sprinkler head into reducer.

Joint the Nipple

25mm inlet end of Nipple with usual jointing compound (e.g. hemp & soap) and install in range pipe outlet.

Note: Do NOT put hemp & soap or other compound on end of Nipple & Reducer which screw into Slip Nuts at each end of flexi-dropper™.

Bend Tube into Position

flexi-dropper™ tube into curve(s) as required in area where the sprinkler head will be located.

Position Caring Bar & Fittings

Slide caring bar through reducer bracket and through the top of the two ceiling grid clamps. Position the clamps on the grid in relation to sprinkler head position and levels in the centre of the tile/board. Loosely tighten all securing bolts.

Check Fittings & Alignment

Once in correct position, firmly tighten all securing bolts and check both slip nuts are tightened. Note: Do NOT over tighten Slip Nuts. They should only be hand tightened as excessive tightening force may damage ‘O’ ring and cause leakage.

Our technical specifications are available in PDF.
Click to view and download .



Consultants Specification

Frictional loss tables

Hydrostatic Testing

YB28 Versus YB25

1. Advantages for Fire Contractors

a) Savings in Labour Cost

  • Increase in labour efficiency, as installation rate is quicker by 2-3 times compared with traditional hard pipe and fitting method of installing sprinkler droppers.
  • One man operation, rather than two men.
  • Install at rough-in and charge system, no need for fit-off test.
  • Reduction in abortive work – no adjustment of sprinkler head needed if ceiling is re-aligned and level changed.
  • No relocation of tools & screwing machine from area to area.
  • No drain down & recharging needed in fit-off process.
  • Easier to bend & manoeuvre in congested spaces and unusual ceilings, e.g. curved plasterboard.
  • Reduce labour cost rates to become more competitive.
  • Can be preassembled with sprinkler head & inner escutcheon plate on or off site to save time.

b) Equipment & Operational Cost Savings

  • Savings on screwing machine purchase, maintenance, repair & transport.
  • Savings on hiring of scissor/boom lifts & scaffolding due to shorter duration required.
  • Savings due to no pipe wastage from off-cut, etc., and reduction in consumables, e.g. oil, hemp, soap, etc.
  • Reduction in non-continuity of work resulting from ceiling grid or service tiles delay.
  • Less risk of water damage to carpet, partitions, etc., as water is charged at rough-in stage.
  • Can be used in conjunction with all types of ceiling grids, e.g. T-Bar, Furring Channel, etc.
  • Re-usable. If they need to be dismantled, they can be re-installed in another area.
  • Avoid overcrowding of manpower, resulting in loss of productivity during fit-off.

2. Benefits of Installation for Sprinkler Fitters

a) Eliminates Occupational Health & Safety Hazards.

  • No accidents from use and movement of screwing machines.
  • No fumes & smoke from screwing machine; reduced skin/eye irritation & inhalation.
  • No more noise from screwing machine; reduced chance of industrial deafness.

b) Eliminates Work Inconvenience

  • Easier to bend & manoeuvre in congested spacing around ducts, trays, etc. and for unusual ceiling types & curves plasterboard ceilings.
  • No need to go back & drain system after ceiling re-aligned & level changed, results in elimination of abortive work, i.e. remove droppers, adjust, reinstall & recharge system, as flexi-dropper™ will move with ceiling adjustment.
  • No need for remote use of screwing machine in areas away from fit-off location, due to builder’s restriction.
  • No drilling restrictions on certain hours for fit-off process, due to public occupation of building.
  • Options available for fitting into tight spaces of less than 100mm in lieu of having to use hard pipe

3. Advantages for Builders

  • All pipe work and fittings (including flexi-dropper™) are installed at rough-in stage, resulting in: 
- Reduced manpower congestion during the critical fit-off stage. 
- No
  • need for pipe, fittings & screwing machines in lifts and on floors during fit-off. 
- Reduction in duration of access times during fit-off. 
- No power tools required for fit-off
  • No need to drain down sprinkler system during fit-off stage, resulting in: 
- Reduction in risk of water damage and delays to finishing trades. 
- 24 hour fire protection.
  • Adjustments can be made to ceiling levels without impact on sprinkler head & droppers after installation.
  • Less disruption to following trades with shorter fit-out duration required.

4. Advantages for Building Operators & Owners

  • Long-term preventive maintenance is enhanced, due to longer life of stainless steel compared to mild steel.
  • Less risk of damage to premises and equipment caused by water leakage or oil spillage.
  • Minimal impact on business operation by reduction in loss of sprinkler protection during tenancy and maintenance work.
  • UL/CSIRO/ACTIVFIRE/FM Approval and Listing satisfy insurer’s requirements
  • Less disruption to occupier during retrofit or renovations: 
- Faster, cleaner, no noise or fumes from screwing machines. 
- Less risk of water leakage, no oil spillage.

5. Advantages of AFT’s ‘flexi-dropper™’ Over other Brands

  • Australian Standards Compliance
  • Complies fully with AS2118.1-2006  CL7.6 (a) (i) (ii) (see product update)
  • Two Models
  • Available in two models – YB28 for Ordinary Hazard & High Hazard and YB25 for Light Hazard – as per AS2118.1-2006

Situations & Solutions

What is the most cost-effective way to install flexi-dropper™


  • Install Flexi-dropper™ during rough-in works.
  • Assemble flexi-dropper™ hose to nipple & reducer, slide reducer bracket onto reducer then install inner escutcheon plate & sprinkler head to the reducer.
  • Fit Flexi-dropper™ to range pipe
  • Cable tie flexi-dropper™ to range pipe
  • Pressure test rough-in piping
  • Leave rough-in piping Flexi-dropper™ assembly charged until fit-off works begin.
  • Fit-off
  • After ceiling grid and service, tile has been installed, reduce system pressure
  • Manoeuvre Flexi-dropper into position in the tile
  • Install & secure ceiling grid assembly onto the grid


If minimal space exists between slab or duct beam and the false ceiling – i.e. 160mm or less what fittings should be used?

Solution Fittings to use:

  • Use Flexi-dropper™ elbow reducer – long radius 160mm steel or short radius 90mm steel elbow,
  • Use standard ceiling grid bracing arrangement for 160mm or 90mm elbow reducers,
  • For spaces, less than 100mm use the Type A Small elbow reducer with L Shaped bracket attached (This is fixed to the building slab & is FM approved)


Tenancy alterations – existing outlets provided within the supply pipework suits the original partition layout. The new partition layout dictates many different lengths between the outlet and the new head location – say between 600mm to 1800mm long. Should I order one length of Flexi-dropper™ and cut varying length arm-pieces in the steel pipe to suit?


No – Order a variety of lengths of Flexi-dropper™. Available in 700mm, 1000mm, 1200mm, 1500mm or 1800mm.


Occasionally, we find that the day after installing a Flexi-dropper™ the sprinkler head has become misaligned and appears crooked, and needs to be re-adjusted.


When installing the Flexi-dropper™ ensure that the:

1: Braiding is not twisted and 
- reducer is securely fixed into reducer bracket without strain in correct alignment


2: Caring bar is clamped to the main ceiling grid runner (not the secondary) 
The reducers can be easily adjusted to the correct position by adjustment of the reducer level by loosening then retightening the two screws at the rear of the reducer bracket.


Installing a ceiling tile, or removing it when the ceiling grid clamp is fitted to the grid or the caring bar is running across the tile to be installed/removed.


  • If the caring bar is running across the tile to be removed, then unclip the ceiling grid clamp after removing the caring bar.
  • If the ceiling tile is adjacent to the sprinkler head, then remove the tile from the opposite end of the clamp and bar.
  • Ensure that the caring bar does not overhang the ceiling grid runner by more than 10-15mm, so it doesn’t interfere with the removal & installation of the adjacent ceiling tiles.


Other trades knock or bend Flexi-dropper™ out of way in the ceiling space, resulting in misalignment of the sprinkler head within the ceiling tile. Occasionally, the whole ceiling grid fixing arrangement is removed by other trades. Can the ceiling grid arrangement be adjusted after the plasterboard sheeting is completed?


Other trades interfering with equipment not their own has been an issue for many years. The only solution to this problem is to have the area inspected by the client immediately after the fit-off has been completed; this will confirm correct sprinkler head alignment. The only way to adjust the ceiling grid fixing arrangement is to access the ceiling space.


How can the Flexi-dropper™ be braced to different ceiling main grid runner profiles?


With Flexi-dropper™ you have a choice of three different heights of ceiling grid clamps (38mm, 58mm or 90mm) to suit different types of ceiling grids.

Refer to Components and Configurations for more detail.

Other Applications


Our Flexible hose fittings for clean room & exhaust ducts are FM approved. We are supplying our clean room flexible hose fittings to Samsung Electronics & LG electronics state of art new factories.

Our products for clean room and ducts were installed at semi-conductor factories and other clean rooms in Singapore, China and other countries.

Our technical specifications are available in PDF.
Click to view and download .


We have three different models, which can be used for the best optimum installation

  • Available lengths: 700mm to 1800mm
  • Approval: FM approved, UL listed.

YB28-I, YB25-I: Reducers and nipples are welded at both ends of the flexible hose. Most commonly used model in clean rooms.

Type I Drawing

YB28-II, YB25-II: Reducer and nipple are connected to flexible hose using nuts. Reducer can be placed first on clean room ceilings and fastened with bolts, then connect flexible hose into the reducer and tighten slip nuts. The work is completed when nipple is connected and fastened onto branch line. This model is a three pieces style and convenient for limited or awkward ceiling space.

Type II Drawing

YB28-III, YB25-III: Reducer is welded to flexible hose and the nipple is connected to the flexible hose using a slip nut. This is a hybrid two-piece model from YB28-I and YB28-II. This model is easy to install and the most recommended model for clean rooms.

Type III Drawing