Unusual Vintage Glass Mortise Lock Thumb Turn Knob

Isn’t this the sweetest little thumb turn ever!?!  The eight sided glass knob is in great shape with no chips and only a bit of minor scratching to the face. There are a few little bubbles inside the glass that is typical of glass knobs from the 1920 – 1930’s era. The setting and back plate is nickel that has not been polished.

Used to throw a deadbolt on mortise locks, these thumb turns were typically used on the inside of doors to bathrooms or bedrooms for privacy. They can also be used on entry door locks where you do not want the option of a removable “key” knob.  If you want to install them separate from your door handles I have a little deadbolt lock that will work with it – DM1045  

Back plate is 1-1/8” x 2” oval
The pin is 3/16” square and extends 1-1/16” into the door.