The Canon EF 40mm f/2.8 STM is an ultra-compact pancake prime lens designed for Canon EF mount DSLR cameras. This diminutive optic delivers a natural, 'perfect normal' perspective on full-frame sensors whilst remaining incredibly portable. The lens features Canon's stepping motor (STM) autofocus technology for silent focusing during video recording, making it excellent for both photography and cinematography. Its circular 7-blade aperture renders pleasing bokeh, whilst the aspherical optical design ensures high image quality despite the lens's compact footprint. The 40mm focal length, combined with a fast f/2.8 maximum aperture and close 0.3m focusing distance, makes it an ideal everyday companion lens.