Medium Rectangular Dam Tray - Fusible Glass Frit Forming Mold This dam mold is a fantastic new concept in frit forming molds! Simply fill the mold with frit, crushed glass, frit balls, stringer...basically whatever you can dream up!....and fire to a full fuse! When the design comes out of the kiln, simply coldwork (if you prefer) and slump into your favorite fusible glass mold or just display as is! No kiln dams required! Yay! Mold measures approx. 8" L x 5" W x 1" H. To use, simply pretreat the mold with kiln wash or nitride spray, and remember to ALWAYS ELEVATE THIS MOLD OFF THE KILN SHELF USING KILN POSTS to avoid mold breakage. This mold creates a slightly beveled edge on the underside of a fully fused glass piece.