 This EF 24–105mm f/4L IS USM lens is available in kits packaged with the EOS 5D Mk II, 5D Mk III and EOS 6D.The EF 24-105mm f/3.5-5.6 IS STM is a newer 'low cost' alternative to the EF 24–105mm f/4L IS USM.It has the same zoom range, but a non constant aperture range which is typical of many non-professional lenses.