"The SB12 is a custom molded soft yellow shaping-sanding block that uses a Velcro hook system to attach our hook & loop 4 1/2"" x 11"" Indasa sandpaper or Abranet sand screen found in the abrasive section. The block is 4 1/2"" x 11"" x 1 1/8"" (3cm x 11,4cm x 28cm). It`s a super flexible block and won`t distort after use. This shaping-sanding block is molded not glued together and is the only one of it`s kind made in the USA. It`s built to last. "