Big Kid Blocks Universal Block Kit - Sphere HandlesBig Kid Blocks are an industry leader in the automotive industry. Their custom sanding blocks are the best in the industry. Big Kid Blocks Universal Block Kit has three 1 4 thick polycarbonate blocks (24, 18, & 11). These blocks have large sphere handles for a comfortable grip. They are our Universal kit because they have such a great mixture of rigidity and slight flex for most applications. SPECIFICATIONS Includes: 3 x 1 4 (approx. 0. 6cm) thick