Sigma 70-300mm Lens With Unfamiliar Pin Configuration

[mr.mike]

Hello and Happy Holidays To All,
Hoping someone might help me identify the camera this Sigma lens is for? It was supposed to be an EF type for Canon, but I've never seen this setup before. I'm familiar with the EF square style 7 pin arrangement, but these pins look rounded. I bought it cheap and plan on using it with my EOS 5 film camera. I looked at many Sigma for Canon lenses, but couldn't find another one like it. Looking forward to your thoughts.
Thank you,

 

[dxqcanada]

That looks like a Sigma SA mount.

 

[mr.mike]

That looks like a Sigma SA mount.

Thank you................

 

[mr.mike]

That looks like a Sigma SA mount.

You are correct, turns out this lens is for an SA mount camera, and I've since cancelled my order. Thank you for your great response. Saved me from a headache.

 

[dxqcanada]