K&F Concept M42-FX IV – M42 Lens to Fujifilm X Mount Adapter

The K&F Concept M42-FX IV adapter lets you mount M42 screw-mount lenses on Fujifilm X-mount cameras. It has no electronic contacts: you focus manually, set the aperture on the lens, and the lens focuses all the way to infinity. The fourth-generation IV PRO adapter has a knurled surface, a brass mount interface and a matte interior that suppresses light reflections.

M42 lenses on Fujifilm X cameras

With the M42-FX IV adapter you can attach M42 screw-mount lenses to Fujifilm X-mount cameras and keep using them on a modern body. The adapter is precision-made, so the lens sits firmly and focuses all the way to infinity.

Fourth generation IV PRO

The knurled non-slip surface with fine CNC engraving is easy to grip, even when changing lenses. The brass mount interface in an aluminium alloy body ensures precise, smooth mounting, and the connection does not deform even after 100,000 mounting cycles. The matte interior suppresses light reflections inside the adapter, and a red dot makes mounting and removal easy.

Manual focus and aperture

You focus with the ring on the lens while the camera works in aperture priority or manual mode. The aperture is set with the aperture ring on the lens.

Camera settings

Before first use, enable the option in the camera menu that allows the shutter to be released without a lens attached (Release w/o Lens). The camera does not recognise an adapter without contacts and would not release the shutter without this setting.

Compatible cameras

The adapter is designed for Fujifilm X-mount cameras, for example Fujifilm X-A, X-E, X-H, X-M, X-Pro, X-T, X-S series.

Before you order

You will find the mount type of your lens and camera in their manuals or in the technical specifications on the manufacturer's website. The M42-FX IV adapter is designed for a M42 lens on a Fujifilm X camera.