Brass Vase Caps are a 3-1/4" diameter. Use as go- between on lamp-body and socket. Use with glass, ceramic, porcelain and metal lamp bodies. Attractively caps off vases and ginger jars. Made of spun brass with a lightly brushed finish. Center hole slips 1/8 IP - 3/8" standard lamp pipe. To assure proper fit select vase-cap by interior diameter .