O-ring Material : NBR. NBR Properties : -20°C to 100°C Working Temperature Range. Suitable Applications : Oil & Grease Resistant, Suitable For Sealing Pipes, Connectors etc. (Not For Drinking Water).
eBay
0.7mm thickness O Ring Rubber Seal Washers Waterproof Round Watch Gaskets Diameter 16mm-35mm 50 Pcs per Size
Aliexpress UK
O-ring Material : NBR. NBR Properties : -20°C to 100°C Working Temperature Range. Suitable Applications : Oil & Grease Resistant, Suitable For Sealing Pipes, Connectors etc. (Not For Drinking Water).
eBay
M56-M48 Adapter Ring Female M56*0.75mm Thread to Male M48*0.75 Thread forAstronomical Telescope Photography Accessories
Aliexpress UK
Imperial FKM Black Rubber O-Rings 1.78 Cross Section BS001 - BS031 ID. All of these designations actually stand for one single base material:fluoro rubber. FKM has a low compression set and have high temperature and chemical resistance.
eBay
Lightdow 650-1300mm Super Telephoto Manual Zoom Lens F8.0-F16 With T2 Adapter Ring for Canon Nikon Sony Pentax DSLR Cameras
Aliexpress UK
O-ring Material : NBR. NBR Properties : -20°C to 100°C Working Temperature Range. Suitable Applications : Oil & Grease Resistant, Suitable For Sealing Pipes, Connectors etc. (Not For Drinking Water).
eBay
StarDikor M48 To M42 Telescope Adapter Ring Aluminium Alloy Female Thread T(M48mm*0.75mm) To Male Thread T2(M42*0.75mm)
Aliexpress UK
O-ring Material : NBR. NBR Properties : -20°C to 100°C Working Temperature Range. Suitable Applications : Oil & Grease Resistant, Suitable For Sealing Pipes, Connectors etc. (Not For Drinking Water).
eBay
M48 To M42 Telescope Adapter Ring Female Thread T(M48mm*0.75mm) To Male Thread T2(M42*0.75mm) Photography Accessories
Aliexpress UK
It has good resistance to many petroleum, grease, hydraulic oil, alcohol, mineral oil and grease. ● [Easy to Use]-This nitrile rubber (NBR) sealing ring has abrasion resistance, pressure resistance, high temperature resistance, oil resistance and waterproof ring seal.
eBay
Food Grade Silicone O Ring CS 1/1.5/2.0/2.4/3.1 Plumbing Gasket Sealing Washer Heat resistance Oil Resistan Faucet Car VMQ Oring
Aliexpress UK
Set of 170 mini o-rings for watches. 0.70 x 0.60mm. 0.70 x 0.55mm. 0.70 x 0.50mm. 0.70 x 0.45mm. 0.70 x 0.40mm. 0.60 x 0.65mm. 0.60 x 0.60mm.
eBay
M42 (T2) - C/CS for M42 x 0.75 (T2) mount - C / CS Mount Adapter Ring M42-C M42-CS for Macro photography for Telescope
Aliexpress UK
O-ring Material : NBR. NBR Properties : -20°C to 100°C Working Temperature Range. Suitable Applications : Oil & Grease Resistant, Suitable For Sealing Pipes, Connectors etc. (Not For Drinking Water).
eBay
EYSDON SCT Male to M42 Male Threads T-Ring Adapter 2"-24TPI Transform to M42*0.75mm Telescope Threads Converter Conversion
Aliexpress UK