Petzl
William Screw Lock

The Petzl William was (and still is) an iconic large HMS carabiner, fully featured for its time with keylock gate latch, gate relief hole, large gate opening and huge basket capacity. Offered in many different locking sleeves, this model uses a large screwlock barrel with a locking indicator. When new, the locking sleeve has aggressive knurling that abrades soft goods and painted gear, but this quickly wears when in a rock environment.

The large size of the William makes it popular as a masterpoint or belay station management carabiner, or as a "do anything" spare carabiner that can hold large objects or many smaller ones.

For this reason, I equip new tree climbing students with at least 1 William - the huge basket holds multiple strands of beginner-friendly 1/2" rope as required by certain rope management or self-rescue techniques.

It does not handle rope quite as smoothly as a round stock carabiner such as the Petzl Attache, and the semi-flat profile is heavier than the modern I-beam version.

This generation of Petzl William bodies has laser batch markings and a mixed case "Pat." marking (with or without the period). Others use stamped batch markings and/or uppercase "PAT"