dinghy snubber: :

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This short video shows how to use a simple snubber to hold the dinghy on the davits.
All you need is a 10ft length of 3/8" double braid a carabiner and a Monster RopeTie.
Compare with stainless steel ratchet systems for $37-$41 which have only one use. This system is easier to use and will not damage the gelcoat or an inflatable dinghy as a metal ratchet with sharp edges would.