RDA Origen V2 RDA O rings size for top cap ?

[BrotherBob]

17 X 2 is what you want. Orings are measured inside diamater X thickness (also known ac CS or cross section)
Buna-N70 hold up really well and are cheep. IMO Viton 75 is the preimum for vape gear, just more $. .06 vs .86
2mm X 17mm Metric Buna-N 70 O-ring [N2.00X017] : The O-Ring Store LLC, We make getting O-Rings easy!
2mm X 17 mm V75 Viton O-ring Black [V2.00X017] : The O-Ring Store LLC, We make getting O-Rings easy!

Avoid silicone for caps, "Silicone offers poor tensile, tear and abrasion resistance, and are not recommended for use in dynamic applications."
Silicone O-Rings - We make getting o-rings easy!

Yep, this makes sense. Thanks montara.

Good idea to save this rubber characteristic site. Simple and easy to use.
re: Contact Us : The O-Ring Store LLC, We make getting O-Rings easy!

Buna N /Nitrile for good abrasion characteristics.