The Q-Series features the unique Twist-Tap™ in-head valve system. The Twist-Tap™ system automatically turns the water supply off when the body is unscrewed. Replacement of the exhausted filter is completed in a matter of seconds by detaching the filter body from a permanent head with a twist of the wrist (hence the Q-Series has also become know as the “Quick-Twist” Series). The new filter body is just as easily threaded into the head and the replacement is complete. With a diameter of 2½”, these filters are available in lengths of 6”, 8”, 10”, 12” and 14”. The Q-Series valve head is available with 1/4" and 3/8" female NPT (National Pipe Thread) or built in 1/4" quick connect fittings.