Pilot Light Heads, ZB4-B Pilot light heads for use with body consisting of either integral LED, neon, or LED The colour of the head should be matched with the same colour of the chosen LED block All heads require a body/ fixing collar, see stock no. 331-0142 and contact bodies, see stock no. 331-0158 etc Schneider Electric ZB4-B & XB4-B Harmony® 22mm Range