Skipping rope, golf club and fishing rod adapter for kids with symbrachydactyly

This is an adapter made for kids born without fingers to hold skipping ropes, golf clubs and fishing rods etc.
It is made out of Ninjaflex TPE. (Do not use hard plastics like PLA, even if thermoformed)
It requires two 20mm width by 300mm length velcro straps to hold it to the arm. They can be purchased at hobby sites like Hobbyking, which are used to hold RC batteries in place.
See https://hobbyking.com/en_us/300mm-graphene-battery-strap.html
Elsewise, you can use 300mm of double sided v