The Yak Attack Screwball 1.0 in. Ball with MightyBolts is compatible with the Wilderness Systems SlideTrax Accessory System as well as other track systems.
The screwball mount with mighty bolts works great with tehGT90 Track system. Also tried the cell blok battery system but found the total weight to cause the Kayak to list. and opted for the track screwball to do the job much better.
Pretty cheap...will split open if you barely over tighten the least little but. Its too loose if you dpon't. I am on #3 now and won't buy another.
Used to hold my Raymarine Dragonfly 5 Pro to the gear track on my kayak. Solid construction and never have to worry about it coming loose.
Great products and the service is totally awesome and fast.