8 foot tube socket, scaffolding with mounting holes, 38.7mm panel, Opening 26mm for KT88 6550 EL34 6SN7 and other electronic tubes Material: Ceramic + Copper Plating Color: Gold Working Voltage:1500V Contact Resistance more than the 0.01Ohm Size(approx):48.5 x 31.5mm Fit for:KT88 6550 EL34 6SN7,ect Package include: 4 x Ceramic Sockets Note: Light shooting 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.