Is the 221.665 On/Off Volume Control Valve Time needed with 231.870 Shower Head?
Would it be considered a "pressure balancing valve"?
Does this shower head not need a "pressure balancing valve"?
It is "Frequently Bought Together" with no mention of what is needed to purchase for the shower head.
The volume control (221.665) is used when using a thermostatic trim (221.616), which sets the temperature only. If you are looking for a pressure balance system the item you will need is 221.606. These are all just trims. Their corresponding valves will be needed in order for the item to function.