The dual, side and centre release options allow easy fitting, even with a lens hood in place. The elasticated cord locates around the lens barrel to retain the cap and avoid loss when the lens is in use.
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VOIGTLANDER Lens Cap 39mm 46mm 52mm 58mm for 21mm F4/25mm F4/28mm F2/15mm F4.5II/35mm F1.2II/75mm F1.8/VM 15mm F4.5III
Aliexpress UK
Universal lens cap to fit lenses with a 46mm filter thread.
eBay
Camera Lens Cap 39mm 40.5mm 43mm 46mm 49mm 52mm 55mm 58mm 62mm 67mm 72mm 77mm 82mm Lens Protector fuji sony Front Lens Cap 1pcs
Aliexpress UK
Universal lens cap to fit lenses with a 46mm filter thread.
eBay
Lens Cap Waterproof Protection Camera Lens Cover for leica 39 43mm 46mm 49mm 52mm 55mm 58mm 62 67 XE X2 XV Lens hood Accessories
Aliexpress UK
Clip-On Lens Cap (CHOOSE SIZE) (sizes 27-34mm button one side larger have one on both sides).
eBay
Pinch Lens Cap Lens Cap Holder 49/52/55/58/62/67/72/77mm Center Pinch Snap-on Cap Cover Lens Cap Protective Lens For Camera
Aliexpress UK
For46mm filter thread size lenses. New Front clip on Lens cap.
eBay
100PCS camera 37mm 39mm 40.5mm 43mm 46mm 49mm 52mm 55mm 58mm Center Pinch Snap-on Front Lens Cap For Camera Lens
Aliexpress UK
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10PCS wholesale For Nikon F mount AI AIS Lens Rear Cap /Camera Body Cap / Cap set Plastic Black Lens Cap Cover for nikon AI lens
Aliexpress UK
Simple clip-on fitting, pro quality. Suitable for all lenses with a 46mm filter thread.
eBay
5/10pcs High quality lens rope Lens Cap Keeper lens cap line For All Cap Holder Safety
Aliexpress UK
Nikkor LC-46B Front Lens Cap Cover 46mm For Nikon Z lenses. Not manufactured by Nikon. Prevent from water, dust, and scratches.
eBay
JJC Filter Adapter Lens Cap Kit for Canon V1 Camera Lens Adapter with Snap-On Lens Cap Kit and Cap Keeper String
Aliexpress UK