Complete 2 speaker 15" Pro-Grade Rubitex Gasket Kit. Rubitex gaskets are constructed of 2 premium gasket materials, (Rubitex and Chip), laminated together. Rubitex is a black rubberized cork-like material for optimum vibration dampening. Chip is a multi-layer compressed cardboard material, as most standard speaker gaskets are made of, for optimum strength, and bonding to the speaker frame. Together they make the ultimate speaker gaskets.