FILL-IT and FILL-IT HTR are sulfur free clays used by mold makers to seal mold boxes, build dams, set parting lines/shims and repair cracks. They are both off white with excellent adhesive and feathering characteristics. They both are also very flexible and will not dry or crack.

FILL-IT is softer than FILL-IT HTR making it easier to handle at lower temperatures. FILL-IT HTR is firmer than FILL-IT and is less sticky at higher temperatures. The smallest amount of heat, just friction from rubbing it in your hands, will soften both products.