For sale is a Sigma 400mm f5.6 prime lens for Canon cameras. This is the HSM (hypersonic motor) version that is not often available on eBay and provides faster, quieter focus than non-HSM APO versions. For DSLRs, it will only work wide open at 5.6, though I've been able to use it with an old Tamron 1.4 teleconverter. Includes original box and a case, but tripod ring broke so it will not ship with one. This is still a very good lens that I have taken a ton of photos with, everything from landscapes and portraits to plenty of youth baseball games.