Which of the following options is NOT an end fitting for blocks?

The correct choice identifies chains as the option that is not considered an end fitting for blocks. Blocks are mechanical devices used in rigging that typically consist of a wheel or a series of wheels housed within a frame. End fittings are components designed to provide secure connections to other rigging elements, ensuring safe lifting and movement.

Shackles, clevises, and swivels are specifically designed end fittings that connect to various rigging gear. Shackles facilitate the attachment of chains or ropes to blocks, while clevises often provide a secure point for linking straps or hooks to blocks. Swivels allow for rotational movement, which is crucial in preventing twisted lines during lifting operations.

Chains, on the other hand, are not an end fitting themselves but are used as a lifting medium or a method of load suspension. While chains may be utilized in conjunction with blocks, they do not serve as an end fitting that directly connects to the block; instead, they are the load-bearing component that may pass through or connect to other end fittings or hardware. Understanding these distinctions is essential in choosing the right components for a safe and effective rigging setup.