It is a private coil stamp from the Shermack Company. They are listed in the Scott US Specialized under "Vending & Affixing Machine Perforations" section (Page 558 of the 2015 catalog).
You will have to ID the basic stamp (the imperf version of the stamp). The values depending on which type it is run from less than $1.00 to $50,00, with most worth a dollar or two.
After you ID the stamp, post the catalog number. Can give you a current value, if you want. Just remember that it is the 2 cent as an imperf that you need to ID from the regular listings.
Imperf coils were made for several companies that had manufactured coil dispensing machines. The perforations vary by machine and by company.
Thank you for all the help, Michael. This stamp was not on any cover, and part of some kiloware I had purchased. I was intrigued, as I had not seen another stamp made like this one.
Thank you again for all the help.
Happy New Year.
Gro