These neoprene sheets consist of closed cell rubber sponge. Closed cell sponge rubber is created by distributing gas through the rubber during production, creating sealed air pockets within the rubber material. Due to these air pockets, closed cell neoprene sponge is softer, more compressible anda superior at absorbing energy compared to solid rubber. Since the air pockets in closed cell sponge are sealed, closed cell neoprene is far less permeable to water than open cell anda thus does not easily absorb moisture. Because of its water resistance, closed cell neoprene is often used as a material for various aquatic applications. Additionally, since it exhibits this resistance to moisture while still demonstrating the compressibility and energy absorption that characterizes sponge rubber, closed cell neoprene rubber is often used in gasketing, where it forms an effective seal between rigid parts to prevent leakage of liquids or gases. The neoprene material also has some resistance to some oils and chemicals compared to other polymers, so it does not degrade as easily when coming into contact with these substances. These resistances enhance the usability of closed cell neoprene as rubber sealing in machinery where such oils or chemicals are present. Color: Black.