You take them in, sign the back, print your address and pay with them. I believe they are rung in as a check, but you can't get any change back. They are good for about 18 months, so I've been saving them to discount my next frame purchase. :-)
I also convinced my LBS to become authorized to take them. It is a bit of a hassle to get approved, but I can use them for anything bike related at his shop. When I tried to use them while buying bibs at Sports Basement, I was told I couldn't use them for clothes. It's how the purchase is entered in to the system...
Anyhow, that's probably more info than you wanted. It's a limited $20 per month, but it's better than a boot to the head!
Kimber
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