Alumilite High Strength 3 flexible moldmaking rubber is perfect for making strong, soft, flexible molds, and great for undercut parts. Easy to use silicone rtv cures overnight. Alumilite Silicone is a 10:1 mix ratio and has a 1 hour open time It demolds in 18 hours and the final mold has a tear strength of 110. Mold can be used in a temperature range of -67ºF to 392ºF. Vacuum degassing is not required. Packaged in a 1 lb container.
So what's the difference between the #2 and #3 rubber? The only difference between the two rubbers is the hardness. The High Strength 3 is softer and more flexible making it a better choice for one piece molds that contain deep undercuts or negative drafts. The High Strength 2 has better dimensional stability and is better suited for less undercut one piece molds and for two piece molds due to the stiffer nature of the cured rubber allowing it to line up better with a second half of a two piece mold.