For several years, I've had two of their larger silicone seals that fit the Long Johnny and an STJ. They've proven to be rugged, comfortable and oil-resistant. My skin is extremely dry, so I usually use olive oil, vaseline or bag balm as lubes. Lighter or water-based stuff just doesn't work for me. These seals have been durable and outstanding. I highly recommend them!
I've also had two other seals from them. One was a poly-vinyl seal for a MonsterTube Jr that started to liquefy as soon as some oil-based lube hit it, and the other was one of their smaller silicone Vel-Seals that fit a cock tube. The Vel-Seal lasted for several years, but it eventually tore. I plan on buying a replacement Vel-Seal, but I'd stay away from their poly-vinyl seals unless you're absolutely sure that the lube you use has no oil (including mineral oil) in it.
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