Estate sale find.
This is a 1950’s era Parker “51” mechanical pencil. Black and metal. (Lustroloy) 
It takes .9mm lead. There are some in the pencil. Seems to be a new eraser.
This seems to be a “demi” version as it is under 5”.
Cap actuated. There is a clutch to load. I put lead in and wrote fine. There are a couple of extra leads under the eraser.
Someone had wrapped some tape under the cap area. I assume to make a tighter fit. I left it as found.
There is a black dot on the jewel. My guess is to help grab the right one out of the pencil cup. ?.? 🤷‍♂️
I was going to try and remove it but thought I could damage it so left it alone.

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