Primo Super Stacker Cribbing Blocks Improved design for use with heavy equipment, machinery, and vehicles. Solid block for higher working load limit. Hybrid profile. Interlocking pyramid design. Working Load Limit: 129,632 lbs (58,000 kg). PSI: 865. Dimensions: 6”(15 cm) x 7” (18 cm) x 24 (61 cm)”. Material: 100% Recycled HDPE, LDPE, PET Plastics. Weight: 27 lbs (12 kg). Made in the USA 15239 No -