Specification: Proof Load: Identification: Common Use: Comment: Commercial 5,000 lb N/A Tandem harness assemblies Manufactured by Parachutes de  France and Strong Enterprises Specification: Proof Load: Identification: Common Use: Comment: Commercial 250 lb RW-3 3-ring release systems Upper riser ring Specification: Proof Load: Identification: Common Use: Comment: Commercial 250 lb RW-4 3-ring release systems Small ring of mini 3-ring systems,  riser guide rings Specification: Proof Load: Identification: Common Use: Comment: Commercial 2,500 lb RW-6 Replaceable 3-ring harness ring Replaces soft RW-1/82 and 83  harness rings. Figure 3-75.  Ring, harness, tandem. Figure 3-73.  Ring, riser, small, 3-ring. Figure 3-76.  Ring, harness, replaceable, 3-ring. Figure 3-74.  Ring, riser, mini, 3-ring. Fasteners Fasteners are various types of devices designed to hold parts  or components together or allow them to be held open or  closed. The most common designs are hook and loop fasteners  (Velcro $^{®}$), snaps, grommets, and slide fasteners (zippers). 3-21