Boating Essentials - Locking Anchor Control - BE-AN-50704-DP This locking anchor control from T-H Marine is made of zinc-plated steel for exceptional durability. Easy to install, easy to use. This anchor control is intended for use with mushroom and river anchors. Zinc Plated Steel Used with Mushroom Anchor and River Anchors Fits 1/4" - 7/16" Diameter Line For use with Anchors up to 20 LBS Easy to install, easy to use