You can find your lens/camera mount in the len's/ camera's original user manual. Or find your lens/camera on the manufacturers' website and under the product specifications look for “mount type”.

• You can mount M42 Screw Mount SLR Lenses to Canon EOS (EF, EF-S) Mount SLR Cameras;
• • All-metal design; hardened anodized aluminum construction,matting varnish inside to avoid light reflection
• • Supports manual control, manual focus, manual exposure and focus to infinity; Red dot mark, high precision, easy to install and remove
• • Canon EOS (EF, EF-S) Mount SLR Cameras - Popular models include: 1d/1ds, Mark II, III, IV, X, C, 5D, 5D Mark II/III, 7D, 10D, 20D, 30D, 40D, 50D, 60D, 60Da Rebel xt, xti, xs, xsi, t1i, T2i, T3, T3i, T4, 300D, 350D, 400D, 450D, 500D, 550D, 1000D
• • You can find your lens/camera mount in the len's/ camera's original user manual. Or find your lens/camera on the manufacturers' website and under the product specifications look for “mount type”.