The first production version of the 58 pattern yoke is subtly different to the more common second issue example. The difference between the two patterns is the lack of loops on the shoulder flares in this earlier version:

The lack of retaining loops is clear in this close up:

The lack of loops shows how webbing design changes over time based on experience in the field. This first pattern yoke was found to be problematic when the large pack was being worn. The 58 pattern pack was held on by two straps and spring clips that passed over the shoulders and secured to the rings on the front. When the pack was being worn, it was found that these straps could slip off the shoulders and so a pair of loops was added for the straps to pass through and stop the straps sliding off.

The fittings are anodised green aluminium, although different variations were available right from the start:

This first pattern of yoke is one of the hardest parts of the first issue 58 Pattern set to find, with many being modified at the time to the newer pattern.