These measure approx. 3/4" X 1/2", and is marked METAL, PAT 1144883; Patent dates to 1966 in the UK! 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 WithAuctiva's FREE CounterEvery buyer gets a MyStoreRewards invitation for cash backPlease email us for details on this item! Unfortunately, we have thousands of items, and no easy way to handle the situation involving HTML hidden wording. We apologize to our customers. Please email us for details on this item! Unfortunately, we have thousands of items, and no easy way to handle the situation involving HTML hidden wording. We apologize to our customers.