By Tube World
EF JOHNSON Type (122-237-1) NOS for 813 power tubes
7 pin ceramic chassis socket
12) with hole in middle
1) with solid center
size = 2 5/8" square
 ceramic chassis mount socket (13 in stock) (813 tube) "Pin It")
 ceramic chassis mount socket (13 in stock) (813 tube)&Category=sockets&ImageURL=http://tubeworldexpress.com/cdn/shop/products/ef237.jpg?v=1633051353){kind=link}