Most probably the unstamped strap commonly seen on unmarked compasses that were issued to SOE/Commando/Parachute troops towards the end of WW2. The strap is single thickness pull through webbing with a shouldered stainless steel buckle and loops. The design of the buckle is very similar to the shouldered brass buckle used on AF0210 straps from 1945, and early versions of the strap used brass hardware.
The AF0210 strap (unstamped), is also found on this compass.
The Vocabulary of Royal Air Force Equipment, Air Publication 1086, Section 6B lists the Mark 7 watch, with a leather strap, and a fabric strap as accessories. Is this the fabric strap? Here are extracts from the 16 July 1963 version of the Vocabulary.
The Mark 7 6B/159 watch was re-cased in 1956 and was still in service for a long period of time.
The Aircraft Navigation Instruments and Equipment items were numbered sequentially as items were added to the Vocabulary, and below is a table indicating the approximate dates of the numbering of various items of equipment. Full versions of the Vocabulary are currently difficult to find.
Mark 7 watch
Strap wrist leather
Mark 8 watch
Strap Wrist fabric
Mark 11 watch
2 prefix added
Compass survival wrist type
Strap wrist watch GS
Strap watch nylon
The 6B/321 strap is listed as an accessory to the 6B/159 watch, but was not contemporary to the issue of the watch, being a later stores spare. The pigskin 6B/169 was a contemporary pigskin strap in 1940, but even the Bonklip bracelet was contemporary in 1956.
A Hamilton 9101000 on a 6B/321 strap is shown at the top of this post.
The SOE/Commando/Parachute Regiment compass was an unmarked Mark 6 wrist compass, the compass dating to WW1, but with no markings, lugs added, and blackened. It was never given a stores number possibly because it needed no identification as it was SOE/Commando/Parachute Regiment equipment, and did not “belong” to the RAF or the Army. However, it needed a strap, and unstamped AF0210 and 6B/321 straps were used, and can be seen on the compass above. It may be that the 6B/321 strap was developed with the compass in mind, and then subsequently used on the 6B/159 watches as these were recased and kept in service.
As the 6B/321 strap was available for use on the compass at the same time as the 6B/159 watch, it is likely to be seen more commonly on compasses than on wrist watches, as the compass was large and in any event was unlikely to be worn daily, and more likely to be put into a drawer for storage.
The AF0210 strap is also (less commonly) seen on this compass for the same reason.
As the General Service watch specification was developed by the joint services in 1948-1951, the Air Ministry agreed to a single thickness, tropicalised khaki strap 5/8″ wide, with stainless steel fittings.
What became the 6B/2594 strap was discussed at several of the working group meetings in 1948/51 and was the agreed DEF-3 strap in the 1951 drawing below. The buckle is no longer shouldered, and is more wire shaped. The webbing and end treatment are identical to the 6B/321 strap.
Photo courtesy MWR member hq-sandman-ute
The 6B/2594 strap was never issued on the 6B/2593 compass although this may have been considered at the time the stores number was issued. This early 1950’s survival compass was issued with a long strap, the 6B/2615.
The GS watch has been seen on the later issued straps, the 6B/2594 and the 6B/2617, and when the 6B/2617 nylon strap fell out of favour, the Mark 11 watch reverted to Bonklip bracelets.
Here is a Smiths DeLuxe on a 6B/321 strap. Photo courtesy MWR forum user Revo
The robust design of the Bonklip means that it is commonly found on the 1950’s issue RAF watches.
We have taken apart the 6B/321 strap from a SOE/Jedburgh wrist compass, and have made a new 16mm single thickness 6B/321 strap. The two original straps are on the left, and third from left.
The 6B/321 fabric strap currently uses our AF0210 buckles until stainless steel buckles become available.
Two straps original 6B/321 straps with brass hardware, and fabric widths of 15mm and 16mm are shown below and the length is about 250mm for the un-shortened strap, with the cut end dipped in dope to prevent fraying.
Our remade 6B/321 straps will be available at either 250mm or 270mm long.