Wide-Angle Rear Window Lens - Driving School Supplies Ltd
Germanium Window 25mmdia x 2mm
Why do camera lenses have small windows which show different focusing distances on the top of lenses? Is it for aesthetics or does it serve a purpose? - Quora
JJC Silicone Lens Hood, Universal Foldable Anti-Reflection Lens Hood Protector for Canon Nikon Sony Fuji DSLR Camera Lens Body Diameter between 53mm~72mm, Glass Window Photography Accessory: Amazon.co.uk: Electronics & Photo
MEDesign products for back pain relief: Kwik Park Lens, Car and Driving, KPL