Odd Stamping on LVS knob- M9

[wllump52]

I recently obtained a black Ray Durham, Giants M9, signature model T141. On the knob is a circular stamp about 1/2 inch by 1/4 inch with the word "TECO" stamped inside the circle--- any thoughts......:confused:

[BMH]

That is the company hired by MLB to grade maple bats.