Packing: 2pcs Material: high temperature resistant ABS insulated seat + phosphor bronze feet Model:GZS8-F2 Terminal: 8 pins size Dimensions: fixing ring length 50mm(1.97in), screw fixing hole diameter 38mm(1.5in), tube holder bottom diameter 20.5mm(0.81in), top diameter 30mm(1.18in)) Fine workmanship, smooth surface without burrs, the tube holder buckle is loose and tight, not easy to damage the tube feet, very suitable for DIY, upgrading gallbladders, guitar amplifiers, etc. Sturdy, not easy to rust, anti-corrosion, durable, not easy to fade, long service life With fixing bracket, can be more firmly fixed tube holders to the panel, to prevent damage to the tubes or PCB board when plugging and unplugging. Mainly used for audio vacuum tubes spare parts. These parts are used with tubes in audio equipment to improve sound quality Suitable for KT66 KT88 6SL7 6SN7 6CA7 6V6 5AR4/GZ34 5R4GY 5U4G 6AS7G 6B4G 6BL7GT 6F6 6J5 6J7 6L6 6SJ7 274B 348A 350B 421A 5691 5692 5693 5881 6336 6550 7199 EL34 EL37 GZ32 GZ34 and other tubes Attention: Please confirm the model number and size before purchase