Boat Collar Fittings



Bit of a handy-man? That's all you need to join the approx 90% of DIY installers. We're available 7 days a week if you have questions at any stage during fitting.


Independent installers and marine dealers who fit Collars are located around Australia. Tell us where you are, and we'll put you in touch. This page is for them, too.


If you're in Queensland and near the Sunshine Coast or Hervey Bay, see the Kapten in Gympie.



Glued &/or welded onto hull


Suitable for

  • Fibreglass & timber boats under 4m, with less than 15hp (simply glued on with no external fixings).
  • Bigger boats that can handle the extra weight of the large metal fixings  required with this system (usually  boats over 4.2m).
  • Boats with restricted internal access, e.g. high sealed floors, double skinned walls, side running seats, etc.

Large boats: Max size Collars only.


Screwed onto hull & sealed


Suitable for

  • All vessels with good internal access.
  • Single skin hulls: plastic, fibreglass, aluminium.
fit their own Boat Collars
Squirting glue behind plates.
Squirting glue behind plates.


Liquid Nails is the only one we recommend or cover with warranty as it chemically bonds to the foam - (think melting together with the foam) - so the foam actually tears before the glue will ever let go - and it takes a LOT for the foam to tear.

Sikaflex on the other hand will stick to the Collar, but under pressure it will peel off the Collar, leaving an almost perfect impression of the foam on its surface.

Therefore, only Liquid Nails Original (or its brother, Parfix), should be used to glue in the internal plates.

The full-length is a major feature that makes KBCs work as well as they do. #1. It turns down the spray, for dry rides. #.2 It produces bow lift, to protect against nose-diving. #3. It provides maximum overall buoyancy.#4. IMPORTANT: if a Collar stops short (is not full length) on a chine fitting, 'green' water can get on top of it during a turn, which has the potential to make it dig in and flip the boat. A proper-length Collar does the opposite, allowing the tightest, most level turns possible.

No, because all screws are coated with Tef-gel, an amazing creamy substance that remains tacky for years, to keep a protective barrier between the stainless steel screws & your aluminium hull.

The Collar itself is fitted tight against your hull and is non-corrosive, being foam. If you use your boat up very dirty creeks or flood waters, and are concerned about debris wedging against your hull, you can run a strip/bead of Sikaflex or silicon around the Collar to seal it, if you want.

Regarding painted boats; factory painted or boats that have been prepped and painted with quality marine paint, won't have a problem with a Boat Collar being fitted. BUT, if you have a hull that's painted cheaply, like with house paint, that was also poorly prepared, it's almost guaranteed the paint will deteriorate and allow water to sit behind the paint and cause corrosion.

Yes, absolutely. Most Collars will fit underneath side pockets, but if the side pocket covers the fixing area, a small pilot hole is required to be drilled through the side pocket (about 12mm diameter). This allows for the long drill bits to pass through, allowing you the right angle etc on the screw heads.

You'll only have to lift your main floor if the floor is 40mm or more above the chine line (side plate meets bottom plate). Most tinnies have the floor sitting just above the chine bar, so doesn't need removing.

If your floor is sealed and/or can't be removed, and is higher than 40mm - you can either;

  1. Raise the Collar so the bottom fixing sits just above your floor.
  2. Use external fixings to anchor the Collar below your floor.
  3. Or, you may be eligible for the new Chemi-Weld fitting method (only suitable for large boats) that requires no internal fixings. Ask us for more info. 

If your boat is over 4.5m long and have either pressed or flat sides, and is either fibreglass or aluminium - yes, you may be able to glue it or weld it onto the sides of your boat, using our new Chemi-Weld fitting method. Ask us for more info. 

Below: click to see your style of boat with a KBC.

Boat's NOT suitable for a Boat Collar

6m fibreglass_sides too curved

*Double skinned, plastic hulls, with no internal access; almost all Polycraft boats, except Tuff-Tenders are ok.

*Boats (particularly fibreglass) with deeply  flared bows/curved-in sides (example shown as green boat>).

*All boats with air-filled tubular sides; e.g. Rigid Inflatables, house boats etc.

*Boats (particularly fibreglass) with near  straight chines; so from the side, it looks like the chine line is almost straight/flat, with minimal rise upwards at bow. (example shown as white 6m boat <).

*Plate boats (larger sizes) with sharp chine rises, or swept-up chines- little boats okay, but not big boats.

*Most catamarans - except little tenders, around 2-3m are usually okay.

*Most boats over 6m - due to weight and size of boat. Only exception is plate boats, that can weld/encase Collar in alloy box. Fibreglass boats over 5m are recommended to fibreglass over the Collars and encase them to hull.

Monark half-cab_too much curve in bow