Discoloration

I was in the SCUBA diving industry about 25 years ago when surgical grade silicone first started to be used in dive mask, snorkels and regulator mouth pieces. The silicone would yellow just from exposure to light and air. If it was against any black rubber even for a short period of time it would take on a brown spot. The color change does not effect the performance of the silicone in any way, only the appearance.

The silicone now appears to be much improved. This silicone will probably last longer than you.

My Swift pillows turn yellow over time. I personally find it must be from wear or cleaning, because the more yellow they get, the more seal problems I have. I replace it with a fresh white seal and I'm set again until it turns yellowish. I have used many cleaning methods from the citrus cleaner to simple step to ivory to dial and results don't change. This is at least how it goes for me.

I had alot of trouble with leaks last night. It frustrated me because I didn't have any leaks the night before. My DME assured me that my interface was brand new but it was definitely yellow when I got it. I told them I would prefer one that isn't discolored and, based on what you say, I'm going to insist on another one.
Thanks for the explanation, Amy

Amy...I also seem to have no leaks one night then the next night I have leaks and am trying to figure out why. I wash my face everynight because I seem to have better luck when I do...I only wash my mask every second day and was thinking that the night I don't wash it I don't get as good a seal. I didn't wash today so if tonight I have trouble I am thinking that may be the reason.