Brookfield Glass Insulator Style CD 121

Looks like another pine green insulator. I was hoping it was green green but no such luck. It is a somewhat small insulator at just under 4" tall but not as small as a telegraph insulator. These were made for telephone lines up until 1921 when Brookfield went out of business. Makes this a genuine antique.
On top is the shop number. The men (and boys) in each shop would be paid by how many they made so a shop number on the top.
The nice thing about insulators is that you can never have too many.