What kind of bellows did I get?

[redshift]

I was hoping to buy an 8x10 bellows for a Sinar P but I ended up with something close but not right. Does anyone know what it fits. It looks a lot like a Sinar. The front mounting flange fits the front standard although it is slightly different. The rear flange is where there are big differences, it's almost 13" square. I know I can make an adapter so that it will fit the Sinar standard. Maybe it will be more useful on the right camera. Can anyone tell what it fits? When both bellows are in the picture the genuine Sinar is on the left. 98072980739807498075

[Sevo]

I have a hybrid bellows that came with a Arca 4x5" Reflex (mounted on a Sinar Norma standard) that is front Sinar, rear Arca. That won't be yours (AFAIK there never was a 8x10 Arca Reflex), but there must have been other (indeed less exotic) cases of hybrid bellows - the Sinar behind the lens shutter is far more common than Arca Reflex bodies, and will doubtlessly have attracted quite a few photographers using other camera systems. Bellows that fit whatever camera on the rear, and a Sinar shutter on the front, with another adapter filling the gap between shutter and front standard, must have been made quite a few times.

[Otto Seaman]

Not sure but you may have gotten a bellows meant for the later F2-P2 Metering Back, which has a different size than the non-metering back earlier versions used by the Norma, F, and P.

Horseman also made cameras that used Sinar 4x5 bellows and lens boards but perhaps their 8x10 version didn't follow the Sinar convention. Inka and some other smaller companies also made cameras that used 4x5 Sinar bellows and boards so it could be something leftover from an oddball prototype or something?

[Bob Salomon]

Again, ask Ulsaker.

[redshift]

Looks like it's my day for odd ball stuff. Thanks again all. kevin