High quality plastic: Designed to stay rust-free and shipshape for a low maintenance high-polish finish that is a perfect addition to any helm One Handed Operation: Designed with precision control in mind this knob is a comfortable 2 1/4" diameter so you can easily navigate your yacht to dock, and enjoy trouble-free trolling Universal Design: Quickly attaches to any steering wheels up to 1" diameter vertically and 1 1/2" horizontally for a fast upgrade and a touch of class All Hardware Included: Clamp assembly, 2 sizes of tightening bolts for large range of size fitments, wrench, and rubber spacers for grip and fitting smaller diameter wheels. Salty Reef Marine Hardware Dependability - Trusted by Boaters World Wide and USCG Approved Seriously....Once you try a Salty Reef Suicide Knob you will never go without it again. 2 1/4" handle with precision bearings and is perfect for maneuvering your yacht to the dock, and stellar for trolling — much easier than hand-over-hand technique. Comes with everything needed for quick assembly, PLUS the positive locking clamp is easy to install and integrates well with any helm - no slipping, guaranteed. Salty Reef Marine Hardware gives you a full line of products that are trusted by boaters world wide and USCG Approved.