Sorry folks, had to have this deleted then repost as I'd put the wrong photos on ...
OK, bought a vintage High Altitude set and to satisfy my curiosity compared it with 40th. I must say the 40th is a very good copy but, there are some easy things to spot.
Looking from the back of the facemask, the 40th mask has a hole right through where the vintage doesn't.
The vintage oxygen bladder (the bit under the mask) has a pronounced bump on the front wheras the 40th doesn't and is more shiny.
The 40th tanks are flat, light silver whereas the vintage have a darker, kind of speckled look.
The 40th frame looks chunkier and is duller. It is thicker in places and has different mould marks which hopefully the pics show. Thicker on the top rail, the segments that seperate the tanks and different marks where the fragile vertical bars meet the second horizontal bar from bottom. Hopefully the pics make it clear but all in all, should be easy to tell the two apart.
Hope this helps if you're looking for the high altitude kit (by the way, anyone got an unbroken frame ? :))
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