Hot block was developed to completely stop the transfer of heat up to 3000 deg F. Very effective when brazing on copper or brass and works as a heat shield when protecting valves and fittings.

Supco® SOLDERWELD® Hot Block Heat Absorption Putty, Composition: Cellulose, Sodium Chloride, Mica, Water, Fibrous Compound Form, Blue

• Hot block is 100% reusable for life and if ever dries up, just add a little water and it recharges to new again
• Blocks direct and conductive heat transfer on all-types of surfaces and metals, including joints, valves, fittings, composite panels, rubber and plastics
• Protect heat sensitive parts and eliminate discoloration, warp-age and distortion
• This putty is a must when protecting reversing valves, ball valves and TXV
• Can be used to hold, align and jig parts for brazing, soldering or welding
• Is effective with any of these heat sources oxy-acetylene torch, natural gas torch, MAPP gas, induction