These measure almost 3/4" X 1/2", at their widest, and are marked as shown in photos with PATENT NO. 2472958, which dates to June 14, 1948. Please look at all photographs, as they are part of the description and ask any and all questions prior to looking. Thanks! Launched from my store - Powered by Highwire.com Track Page Views With Auctiva's FREE CounterEvery buyer gets a MyStoreRewards invitation for cash back