Seymour was really ahead of his time on this one. This is a 60w all valve combo amp, but in a fun twist, you can switch preamp modules to get different amp tones. It's currently in a Deluxe Reverb style mode, which sounds great: thick and full on the lows with sparkle and chime on the top, with a very usable reverb. You can get all manner of other preamp modules covering other tones if you dig around.... it's kinda like the 80s era hardware version of the a Helix. 

Model: Seymour Duncan Convertable 60
Made: USA, 1986 approx (serial 06-1385)
Output: 60 watts
Speakers: Duncan 12" 75w 
Housing: plywood cab
Finish: black tolex
Weight: 22kg approx
Extras included: non-original footswitch, extra preamp module, some printed info

Condition notes: used, tested and fully functional, few minor marks. Overall: very good condition (7.5/10)