Camera Accessories
500mm F/6.3 Manual Focus Prime Telephoto Lens + T2 Lens Mount Adapter Ring, Astronomical Photography Telephoto Lens for EF Bayonet Lens (White)
Optical Design: 4 groups of 4 elements of optical structure, multi layer MC coating can suppress lens spot and ghost, improve contrast and color authenticity. Lens Type: A accuracy achromatic refractor design for nice peak contrast and flare control...
https://www.bizrate.co.uk/cameraaccessories/500mm-f-6-3-manual-focus-prime-oid26763334410.html