New OEM Attwood Black tri-lobe knob to fasten their two-piece, pivoting, cam-lock style, pivoting, folding nav lights, commonly found on boat bimini tops, arches and spoilers. This black knob will work in either the Zamak alloy (chrome) or stainless steel versions of the lights. Attwood part number 001003167 When you lost your knob, the nylon washer (part number 001003166) probably disappeared too - one of them is included with your purchase. Listing is for ONE KNOB + ONE WASHER. Not any kind of light or base. Pictures of the light bases are for reference only. Default shipping is USPS Ground Advantage. USPS Priority Mail expedited shipping available.