Well the top strap is found on Swiss medic's pouches and that one could be carried in front by fitting the extra strap along the waist belt at the back and hanging the pouch over the shoulders in front of the soldier.
The pouch was made in a way that it folded open completely to get to all the contents.
The other two straps can be found with 06/29 and P49 holsters. I assume that these were used in the same way as the above one so to be able to carry the pistol in front of you.
This was more convenient in for example armoured vehicles and tanks that had quite narrow entrances (think of the post war AMX 13 light tank).
Some P49 holsters also had an extra stud fitted at the back of the holster to be able to carry the holster with opened flap and I think that was for the same purposes.
The straps for the medical pouches can also be found on holsters and I made the picture to show some differences.
For the medic's pouch the extra strap is 29cm or 11.4" long measured from the rivet to the end of it.
For the pistol straps this is 24cm or 9.45".
Most straps for medic's pouches use buttons for adjustment while most military holster straps seem to have buckles.
Thanks,
Guisan.
