Ok so I recently picked up a few Carlos Santana Indians game used bats. The bats were cupped and had writing inside the cup. I am more of a jersey guy than a bat guy and was wondering if someone could offer some insight as to the writing inside. Below are a couple pics of a few different bats.

First two numbers represent length and weight and then a date. Any insight as to the additional writing or the significance of the date (production, delivery, use??). Thanks in advance for any insight.