shackle:  a U-shaped load-bearing connector designed to be used with a removable pin .

Types：

(a) Body types covered are anchor, chain, and synthetic sling (see Fig. 1).

(b) Pin types covered are screw pin and bolt-type (see Fig. 1).

Use：

(a) The screw pin shall be fully engaged, with the shoulder in contact with the shackle body (see Fig. 2).

(b) If a shackle is designed for a cotter pin,it shall be used and maintained in good working condition.

(c) Contact with sharp edges that could damage the shackle should be avoided.

(d) Shock loading should be avoided.

(e) The load applied to the shackle should be centered in the bow of the shackle to prevent side loading of the shackle.

( f ) Multiple sling legs should not be applied to the shackle pin.

(g) If the shackle is to be side loaded, the rated load shall be reduced according to the recommendations of the manufacturer or a qualified person (see Fig. 3).

(h) The screw pin shackle shall not be rigged in a manner that would cause the pin to unscrew.

(i) For long-term installations, bolt type shackles should be used; if screw pin type shackles are used, the pin shall be secured from rotation or loosening.

(j) Shackles should not be dragged on an abrasive surface.

(k) Multiple slings in the body of a shackle shall not exceed 120 deg included angle.

(l) When a shackle is used in a choker hitch, the pin shall be connected to the choking eye of the sling.