TOOLEE GROUP INC.

• Do not replace the shackle pin with a bolt . A load will bend the bolt.   

•  Do not allow a shackle to be pulled at an angle. The legs will open. Pack the pin with washers to center the shackle.

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   Do not use screw pin shackles if the pin can roll and unscrew. If the load shifts, the sling will unscrew the shackle pin.

This is the basic situation which you should avoid , understand it ,you can use it better.

From CCOHS.