Military Token. Obverse; BRITISH ARMED FORCES, a shamrock, a thistle & a rose, Reverse; HALF UNIT, a shamrock, a thistle & a rose, 20mm with central hole, 1.94g, nickel-brass, struck by the Royal Mint, Yarwood-BAF3, NEF.
Reference; John F. Yarwood, A Guide to British Military Tokens , 1998.