Loadrite single boat c420 trailer with Dynamic Dolly loading system. Originally purchased at Colie Sails in 2019, I don't believe it has ever left the state in NJ. Priced at 50% off retail and in excellent condition.
https://coliesail.com/accessories/trailers-accessories/420-single-boat-trailer-system.html
Note: you need a dynamic dolly (not included) to slot it into the frame, as pictured on the Colie Sails website.