9 x 12 x 24 Ballistic rubber blocks; Modified Butadiene Rubber (SBR). Similar properties to NR but with improved aging and temperature resistance.   Flame Resistance: Good (See ULReport)  Sunlight Resistance: Good   Weather Resistance: Excellent  Water Resistance: Excellent Flame Resistant Formula, High Quality Materials, Provides Range Safety, Easy Install. 107 lbs. per unit