Teflon is a remarkable substance. It has the best resistance to chemical attack of any polymer, and it can be used at any temperature between -73 C and 260 C with no effect on its properties. It also has a very low coefficient of friction.
A stale dated warrant is an unredeemed warrant which was issued more than six months prior to the current date. A stale dated warrant is expired and the original instrument is no longer negotiable.
Sell-By Date: Refers to the last day a retailer can display a product for sale; typically a food is safe to eat for 10 days after the Sell-by Date if refrigerated properly. Use-By Date: Refers to the last day a product will maintain its optimum freshness, flavor, and texture. Beyond this date, the product begins to deteriorate although it is still edible. Expiration Date: Means what it says - if you haven't used a product by this date, toss it. Zuckerbrot pointed out a surprising fact: with the exception of baby food and infant formula, dating is not required by U.S. federal law.