This is a Sirui-made lens that comes with auto focus to give you the best setting for each picture. If you want to use a filter on the lens, then the filter size is 67 mm.
From WEX Photo Video
SIRUI 50mm f1.8 Anamorphic 1.33X Lens for Sony E
Camera Centre
Sirui 50mm F1.8 Anamorphic 1.33X Lens - Sony E Mount
This product is also available at 1 unverified store.