>>3973955I believe it's similar to the older 45mm f1.4 model. I haven't tried any of them, though. This review (
https://www.photographyblog.com/reviews/irix_45mm_f1_4_gfx_review) says:
>The lens barrel uses a combination of reinforced magnesium and composite elements with a reinforced metal internal construction and it's fully water-proof thanks to seals in 5 key locations. I don't mind plastic barrel at all, but plastic mount is where I draw the line.