Amarine-made Aisi 316 Stainless Steel Marine Sport Boat Steering Wheel Knob with Plastic Cap, Maneuvering Knob - M Made of Aisi 316 Stainless steel 316 Fits most steering wheels with rim dia. from 5/8" to 1". All Stainless Steel Steering Wheel Maneuvering Knob With Plastic Cap