Six Belton Nine Pin Noval Bottom Chassis Mount Brown Micalex Tube Sockets For 12AX7, EL84 6CA4, 6DJ8 And Similar Miniature Nine Pin Noval Based Tubes. Micalex body, tinned saddle, fine contact integrity. Mounts below the chassis through a slightly larger than .725". Mounts to chassis with two machine screws, mounting centers approx. 1.114". Height of phenolic is around .098" making these a good choice for bottom chassis mounting in Hammond and similar chassis but probably not for extra thick metalwork.