Leica lens with an "a" in serial number

[goldian]

Hi All
Have bought a 1930s leica lens with a serial number with an "a" at the end looking like added later - any one have an idea as to what this means please?

thanks
Ian

[ian_watts]

Might be a duplicate serial number being differentiated with the 'a' (though I think Leica usually use an asterisk in this situation).

[Roger Hicks]

"attrape" = dummy. Some attrape lenses were converted to usable, especially during WW2. I once had a fat barrel coupled a* 90/4, possibly the only ever a*. It 's in a couple of books).

Cheers,

R.