Boat Collars for Roof-toppers

Whether you've been using a roof-topper for years, or about to buy one and start exploring, this page is focused on the common roof-topper questions related to the Kapten Boat Collars.

We understand you're limited to what size boat you can have due to the weight restrictions of your vehicle's capacity, car's width, &/or loader's restrictions.

Most car-toppers are a maximum of 3.8m long, but the majority are around 3.2m - 3.5m, which often means the boat is unstable & prone to capsize.

When you've got a tippy boat, the crew are frequently wary, concerned with their position & movement in the boat, which doesn't make for pleasant trips on the water.

But with a truly stable, and unsinkable boat, where you're free to move & stand, you can fully relax and enjoy your adventures, making every trip fun, safe and rewarding for everyone.

349 Stessco Bream tinnie with Kapten Boat Collar fitted.


Q.1 - Best boat shape?

Q.2 - Rear vs Side loaders?

Q.3 - Extra width when loaded?

Q.4 - Tie down methods?

Q.5 - Weight & sizes?

Standing at the edge of a stabilized 3.3m Savage Gourame - with Max-66 Collar

Question 1. - Do you recommend a certain boat shape to suit the Collars?

The classic shaped boat is certainly the best. However, we can fit Collars to almost every boat shape there is, but may not be able to cover the entire bow of the boat.

If the Collars don't go to the very nose of the boat, it's not a big deal for most roof-toppers, but if you're planning on the close offshore trips, or semi-open waters (big lakes etc) where chop can get pretty big, a classic shaped boat will provide a full length Collar which will give you lift at the bow to prevent nose-diving, wave piercing & provide maximum spray diversion.

Classic shape. (The best!)

3.7m Quintrex Dart made stable with a Kapten Boat Collar, Max-66

Some classic style tinnies:

  • Bluefin Varmint
  • Quintrex Dart
  • Savage Snipe
  • Horizon Angler
  • Ally Craft Cody
  • Stacer SeaSprite
  • Stessco Bream


Modern / swept-up chine.

359 Stacer Proline, with swept up chine design. The Max66 Collar has been custom shaped to suit, but must end a touch short.

Some swept-up chine boats:

  • Stacer Proline
  • Quintrex Explorer
  • SeaJay Nomad
  • Makocraft Topper Tracker

V-nose / flat nose punts.

3.6m Horizon V-nose punt with Max-66 Collar.

Some V-nose punts:

  • Clark Predators
  • Quintrex Wanderer
  • Stacer Skimma
  • Ally Craft Lizard
  • Horizon Square Punt (flat nose)

If you're unsure which boat will best suit your needs and the Collar, feel free to give us a bell as we're happy to discuss this with you and help you come to a confident decision.

Question 2. - Which boat loader is best?

We've not come across a loader yet that was restricted or hindered due to the addition of a Boat Collar. However, some loaders; greater protect the Collar, make it easier to load, and easier to lock into position on the roof. Lets take a look at a few examples...

(No brands are discussed, just their function).

Rear-loader working smoothly to lift this 379 Stacer Nomad onto the roof.

The rear loading system requires the boat to lay in the upright position behind the 4WD, before being winched nose upwards onto the racks. The Collars don't interfere with the winching.

Collars don't contact the ground, or the racks, so this style of loading protects the Collars the best.

Super easy with the winch. Just gotta make sure all the ropes etc are hooked into their correct spots before starting the winch.

Bob's 3.7m Quintrex Explorer with Mini Collar & Transom Foam
SIDE LOADER - winched v's muscles
3.8m Bluefin Varmint being winched onto roof by side loader.

When the boat rolls on the Collar, this doesn't hurt the Collar, but it will get scratched if rolled on gravel or rough bitumen.

The 3.8m Bluefin Varmint (on left), was fitted with a pair of 1.2m long BC Shields, which not only protect most of the side when rolled on, but also protects it when hauling up crab pots etc. (More info on the BC Shields coming)

Whether it's winched (above/left) or pushed (below/right), the boat must roll on its side, & thus on the Collar, before being flipped onto the tracks/skids in order to slide up onto the roof racks. It is pushed or winched onto the roof and adjusted into the correct position.

370 Quintrex Explorer, pushed onto roof by hand with side loading skid system.

QUESTION 3 - How much extra width will the Collar add on the roof-racks?

3.5m Quintrex Dart with Max Collar

Above is a 3.5m Quintrex Dart roof-topper from all angles. Because the Max-66 Collar is fitted at the chine of the boat (lowest part of the side) as usual, so it isn't close to the gunwales of the boat, therefore is quite a distance from the roof-racks of the car.

Due to the varying angles of the sloping sides of different boats, it is impossible say exactly what the additional width for each boat & Collar will be, however, from the arrows placed onto the above images, it is evident the additional overall beam is only a few centimetres, and for this 3.5m, it stays within the loaders overall width.

Mini Collar on 3.45m boat.
Mini Collar 100mm W x 160mm H.
Max Collar on 3.5m boat.
Max Collar 140mm W x 240mm H.

QUESTION 4 - How can I hold it down without damaging my Collar?

Ratchet straps with Straps Protectors.

The most common practice of tying car-toppers down, is to use a couple of ratchet straps. This will place pressure on the Collars, due to the reverse chine shape now added to the boat (see above profile photo).

To prevent undue stress on the Collar, you can purchase Strap Protectors (or make your own) - which will spread the load across a larger area - or chose a different tie-down method for your boat.

Our Strap Protectors are pressed from 3mm alloy, hole punctured to allow even large straps & buckles to pass through, and cupped each end to secure it onto the Collar. They're $79 a pair incl GST.

If you like to really crank your boat down super tight, this system may not be the best for your Collar, so we suggest you consider the below/next option - Bruce's bolt method.

370 Makocraft Topper Tracker, with Boat Collar & Strap Protectors under straps.
Alloy covers
Strap Protectors for Boat Collars are $79 a pair, incl GST.
Bruce's bolt-down method = no straps needed.

Bruce came up with this method for his 3.8m Bluefin Varmint, and we think it's very clever & simple way of really securing your tinnie without the need for super tight straps over the top.

Drastically reduce the risk of breaking a window or denting your car from throwing heavy ratchet straps blindly over the top of the boat - this method requires a thick pad of aluminium to be welded to 4 exact spots on the gunwale of the boat, so that they line up perfectly with your roof-racks.

Once on the rack, a long bolt is passed through the pad and the roof rack (which needs to be drilled through), and a washer and nut holds the bolt firmly in place. No room for the boat to move, and if one bolt did come loose, you've got 3 more holding it down.

Bruce's method was shared & discussed on our Facebook Group page, 'Kapten Boat Collar Club', and a fellow customer suggested a longer bolt be used so a pin could be placed at the end for added security. Always better to be safer than sorry.

Other great ideas customers have had:

  • attached hooped stainless eye-bolts (not sure if welded in), at 4 points on the gunwale as well as the outermost part of the racks and cranked the boat down tight using stainless steel hooked turnbuckles.
  • strapped boat down by the inside seat, instead of over the top, and then tied bow to bullbar, and transom handles to the rear bumper (a lot of straps are needed).

QUESTION 5 - How much extra weight will the Collars add?

A common and very important question, is how much weight will the Collars add.

This will depend on the style and size of your Boat Collar, but as the Collars are made from closed-cell polyethylene foam, they're very light and not much weight in them at all.

Weights are approximate only:

Mini Collar

(100mm W x 160mm H)

2.5m boat = 4-5kgs

3m boat = 6-7 kgs

3.5m boat = 8-9kgs

Slim Collar (new)

(100mm W x 240mm H)

2.5m boat = 5-6 kgs

3m boat = 7-8 kgs

3.5m boat = 9-10 kgs

Max Collar

(140mm W x 240mm H)

2.5m boat = 6-7 kgs

3m boat = 8-9 kgs

3.5m boat = 10-11 kgs

3.8m boat = 12-13 kgs


Office: (07) 5481 6133
Mobile: 0423 499 047
760 Bruce Hwy, Chatsworth, Qld, Australia, 4570.


Australian Patent # 2010201449. American Patent Application # 13/083,588 - Watercraft Accessory.
Marine Safety Innovations Pty Ltd.
ABN # 53 141 908 385
Australian owned & operated since 2010