Abstract: A surgical tool that includes a sterilzable handpiece that receives an aseptic power module. The handpiece includes a data tag that contains data identifying the type of handpiece. The power module includes a reader that reads the data from the data tag. Based on the type of handpiece the power module selectively actuates the power generating unit internal to the power module. Specifically, the power generating unit is actuated to output energy having the appropriate characteristics for the type of handpiece to which the power module is attached. In many versions of the invention, the data tag is mounted to the latch integral with the handpiece. The power module also interprets the receipt of the data from the handpiece as an indication that the power module is properly latched into the handpiece.