Here's a really handy accessory for tube amp builders. Use this plate and socket and you won't have to drill a bunch of ventilation holes in your chassis. Industrial matte finished aluminum plate measures 2.677" X 2.677". Socket hole 1.417"/36.01mm, tube socket screw mounting centers 1.841"/46.77mm. While we suspect that most of you out there will be using this plate with an 'antique' triode four pin Johnson style wafer tube socket as depicted, you should also consider that the plate accepts very nicely all of the 5 pin, 6 pin, 7 pin and 8 pin wafer sockets we offer.