The National Porcelain Company of Trenton NJ is probably better known for its electrical insulators but, just prior to WWII they started dabbling in what was described as "electrical porcelain, bathroom fixtures, vases and miniature novelties and china" Around 1937 the introduced a pair of ashtrays. The aptly named “Snuff a Rette” and the Guardsman “Safety” Ash Tray.

This is an example of the “Safety” a very heavy 4”x3” chunk of porcelain. As the instructions on the back explain the Safety part of the device “Place the cigarette in grove will snuff out at edge protects your furniture”