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CPL04 Coupling is intended for use in FR Slab wagons, both long and short code FRB03, FRC03, FRB07, & FRC07. Don't confuse with CPL05, which is narrower having only one fixing bolt each side of the buffer and is used on Gunpowder vans.
Will require splitting down the middle into two couplings.
Attach tail to wagon using 16BA nut and bolt, or better yet an M0.8 Hex headed nut and bolt from Prime Miniatures.