Alumilite High Strength 2 Tin-Based Silicone Rubber 1lb
High Strength 2 is a tin-based silicone mold making rubber with high tear strength and is great for making all types of molds - it's soft enough for 1-piece molds with undercuts and strong enough for 2-piece molds with secure alignment. Use Rubber to Rubber mold release or petroleum jelly when making 2-piece molds.
Doesn't require degassing, but recommend when possible.