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.
For the best answers, search on this site https://shorturl.im/9vENT. A personal check is stale-dated after 6 months. I would not recommend trying to cash or deposit it, as your bank will probably charge you the returned check fee.