PME square plunger cutters, S/M/L set of 3 (MS152). ABS thermoplastic. Official sizes: small 6 mm (0.2"), medium 10 mm (0.4"), large 13 mm (0.5"). Official materials: sugar paste (rolled fondant), petal paste (gum paste), marzipan, and craft clays. Specs from PME's Shapes Plunger Cutters - Square page.
Three miniature square plungers. Same millimetres as the round set.