The Bullhead case requires a special stepped profile crystal in order to seat correctly within the case and provide the correct clearance for the chronograph hands. The Seiko Bullhead does not use a standard flat crystal.
Crystal Glass Gasket For Seiko Bullhead Bull Head 6138-0040 6138-0049
Crystal Glass Gasket For Seiko UFO 6138-0010 6138-0011 6138-0012 6138-0017
GENUINE USED STELUX FISHBONE BRACELET SOLID LINK SEIKO PANDA 6138-8020 6138-8021
Replacement Part Watch Dial Seiko CRONO 6138-3002.
Seiko SKX007 SKX009 Replacement Mineral Crystal – 31.5mm Flat Diver Glass
NEW MINERAL GLASS CRYSTAL LENS VINTAGE SEIKO 6138 6138-0040 6138-0049 Bullhead