fixed master造句

The'old style'fixed master socket had only one set of terminals on the back and customers were supposed to use extension kits plugged into the front socket; however, many customers hard-wired their own extensions anyway for neatness and robustness reasons, which was a poor arrangement since it provided no way to isolate the customer's internal extension wiring from BT's wiring.
It's difficult to find fixed master in a sentence. 用fixed master造句挺难的