Tough-Cast 65D is a two part casting resin that is virtually indestructible. It's designed to make durable prototypes, and reproductions.
Smooth Cast 65D - Semi-Rigid Urethane Casting Resin - Pint Unit
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Cast Urethanes - Rigid, Flexible, Water Clear Urethanes, Silicone
Tough-Cast 65D
Tough-Cast 65D
Specialty Resin & Chemical: Casting Resins and RTV Silicone Rubber
Smooth-Cast 65D 1.9 lb by Smooth-On, Inc. : : DIY & Tools
Figure 4 Tough 65C Black
Cast True Blue By Siraya Tech (0.5kg for CA)
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TC-1630 UltraCast, Fast, Tough
Tough-Cast 65D Black, Specialty Resin
Tough-Cast 65D
TC-1630 UltraCast, Fast, Tough
Smooth-Cast™ 65D Product Information