Cape Dory 25, Slot= 4.2", TD=16.44mm

You may dye the White Nylon surface to a color.  Black is best for UV blocking and Orange is best for new crew orientation.

This insert designed for a Spartan mast used on a 1981 Cape Dory 25 with a feed slot cut out = 4.2" x 1/2" and
Track Depth = 16.44mm

Iteration version: "pg512A Cape Dory 25 C2 TD16.44 L107.v100.7"