DCMaster Operating Module

Okay, I am considering purchasing a PCM PRR M1a in N scale with the LOKsound system. But, since I do not have DCC, it would be running on DC. The website says it requires a DCMaster Operating Module for operation in DC.

[?]What is a DCMaster Operating Module, where can I get one, and how much does it cost?[?]

A Google search wasn’t any help…[:(]

It’s on the PCM site, in the full list of products.