POLYFORM-Oven Bake Clay Template. This template is designed for making the perfect oven bake clay balls ranging in size from 1/8in (3mm) to 1-1/8in (28mm) for Premo Sculpey; Sculpey III; Fimo Soft; Classic and Cernit and Studio by Sculpey clays. Template is constructed of translucent; flexible plastic. Made in USA.