Duncan Bloomfield fat.drummer@tesco.net

I am the proud owner of this 1975 signature series kit.The kit is still used regularly for gigs.

(actually, it's an anniversary badge Phonic kit, but it's still very nice)

I would be interested if anyone could identify exactly what model the snare drum is.
I have looked in some pretty old sonor catalogues but have never seen the snare drum in them.
Any ideas?

( It's a D505 5.75x14 ferro)

Duncan Bloomfield, (Hertfordshire,England)