This is a Canon Bellows FL made for use with the Canon cameras and lenses.  It will work with Canon FL and FD cameras.  I checked the fit on an F-1 and FT.  The bellows is in like new mechanical condition and is light tight. It is in excellent cosmetic condition, with slight signs of use.  The extension knobs turn smoothly, and the camera clamp ring tightens as it should.  This is the best engineered bellows I have ever seen.  Includes an instruction manual.