The distinguishing features of the pear-shaped Petzl “William” Carabiner are its large size and wide opening. All Petzl carabiners are made from 7000-series aluminums, a high strength rod stock, thus, with the William you are assured of an alloy that balances breaking strength, weight, and durability.
The large size of the William means that it is perfect for belaying and rappelling with the Munter or Italian hitch with either single or double ropes. It can also anchor multiple ropes as well as slings. The wide opening assures quick and easy clipping of ropes and large-diameter bars. These features also allow easy operation even with gloves on.
The William is available with either a manual or automatic locking system. The manual locking model uses a screw-lock (SL) that you have to twist after setting the gate in its locking position. A red band indicator around the locking area provides a quick safety check. It should be concealed if the mechanism is properly locked.
With the auto-locking systems, the carabiner automatically locks when the gate is set in position. These consist of the ball-lock (BL) and the Triact-lock (TL) systems. The former uses a push-button ball to unlock the carabiner, while the latter opens with a spring-loaded rotating sleeve.
One advantage of manual-locking mechanisms over the auto-lockers is that they are less prone to malfunction in dusty and dirty environments. On the other hand, auto-lockers are quicker at clipping and locking attachments. Regardless of the preferred mechanism, the gate and body interface is snag-free and will not interfere with the rope or anchor.
The William comes with a dark gray frame and polished gate. The sleeves of the SL and BL are also polished, while that of the TL is colored orange.