What type of bolt is used when the lead to height ratio is 1-1/4 or less?

The correct choice is the straight eye bolt, which is specifically designed for applications with a lead-to-height ratio of 1-1/4 or less. This type of eye bolt features a vertical eye that allows for the attachment of rigging components or lifting devices. It ensures a direct line of pull, making it suitable for situations where the load does not exceed the specified lead-to-height ratio. This design helps in minimizing stress and maximizing the efficiency of the pulling force, contributing to safer and more effective rigging practices.

Other types of eye bolts, such as thimble eye, loop eye, and diamond eye bolts, are generally intended for different configurations or load distributions. They may not provide the same level of direct pulling capability that the straight eye bolt does under specified conditions. By understanding the roles and designs of each type of bolt, one can determine the appropriate choice based on the specific load and application requirements.