This is another hone I recently picked up and have not had much luck finding information on the forum.

It is 2 1/2 by 3 7/8 inches.

Manufactured by Bickett Rubber Products Corporation
Watertown, Wisconsin, USA

it is a man made barber hone. The hone I picke dup is new in box and shows a price of $1.50. All identification on hone is on back. It is interesting that the text on back has a double strike (for lack of better terminology) on the ETT in the name.

I will get pictures up soon.