The EF40mm f/2.8 STM was a standard prime lens which was introduced by Canon in June 2012, alongside the EOS 650D/Kiss X6i/Rebel T4i.Technical data of the Canon EF 40mm STM The lens features a maximum aperture of f/2.8. It was Canon's first EF pancake lens. The EF 40mm was the first EF lens equipped with a stepping motor (STM). It was discontinued in March 2021.
See also Pancake lens
References
External links
EF40mm f/2.8 STM - Canon Camera Museum