Pixco M42-Fuji X "Speed Booster"  type_Power & Cables but that's not the case:

but that's not the case: you can use this lens on anything with an M mount

It looks nice though

including light brassing at the edges and a shallow ding on the rear winder-side corner

2L II lens is a specialty short telephoto lens with a fast f1

Shutter speeds are good

Pixco M42-Fuji X "Speed Booster" &nbsptype_Power & Cables but that's not the case:Not a real "Speed Booster", because that's a Metabones trademark, but same idea: this adapter to mount M42 lenses on a Fuji X camera includes a focal reducer to eliminate the Fuji sensor's 1. 5x crop. Extra benefit: you gain a bit of light. Downside: corners can get soft wide open. It's not perfect, but it's a pretty decent solution if you want to pretend you have a full frame camera.