To increase the friction and reduce movement you can place a rubber pad between the kayak surface and the bottom of your cooler.
Diy kayak cooler bag.
The bag coolers are known to be more suitable for narrow kayaks with limited space.
This is because the bag coolers are designed to come in more compact sizes than the box kayak coolers.
The box kayak coolers on the other hand are best for recreational kayaks.
Apply as much pressure as you can to prevent your cooler from sliding on the surface.
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To secure your cooler you just need to run a velcro strap through each plastic buckle of the cooler and then secure it to the kayak.