Install this Tiller Lock Box in your cockpit coaming, drop the twist-lock telescoping tiller extension in, and you have instant self-steering.Holds any ball-grip adjustable tiller extension in place for short periods of self-steering. Adjustments are made by adjusting your tiller extension length.Key FeaturesCutout dimensions: 3 1/2" x 2 1/8"Flush cover plate: 4 3/4" x 3 3/8"Fasteners included