This is an access cover plate on the outer boom of a Century Modular Midnight Express/300 Series/211/212, Vulcan 804/807/806/810, and Holmes 440SL by Miller Industries. See Brochures for a reference chart and Features for related parts.
Related Parts:
Outer Boom (12-0807002)Main Boom (810210000)Main Boom (12-0804262)Main Boom (12-0807653)