DURA CRIB® Super Crib Jacking and cribbing blocks are a purpose built tool designed to replace unsafe timber blocks that had traditionally been used to stabilise machinery and equipment used repair and maintenance or storage. With a working load limit of 51.7kg/cm2 enables these tools to be used to stabilise heavy machines and equipment. The Super Crib Jacking and Cribbing block is an excellent alternative to steel vehicle and equipment stands. The unique interlocking feature of this jacking block ensures the safest cribbing block box stacks when working on machines and equipment. In addition, the pyramid profile surfaces facilitate a secure top and base that can be used on non-square cribbing block stacks.