Precision cast marine grade stainless steel. Mirror polished, corrosion resistance and durable. The standard deck fill key fits the slot and holes. Stainless steel chain to avoild losing or misplacing cap. There is a small rubber gasket at the base of the cap for a good seal. Total Height: Approx. 1.6 cm / 0.63inch Thread Diamter: Approx. 4.2 cm / 1.65 inch Surface Diameter: Approx. 4.5 cm / 1.77 inch colour: silver Material: stainless steel Package Contents: 1 x Boat Deck Fill Replacement Cap Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.