Do I need a Kohler K-300-K or K-301-K?

I got a great question asking if a Kohler K-300-K can be used in place of a Kohler K-301-K:  “In your listing, you put that this faucet set can be used with either the K-300-K or the K-301-K rough in valve. On Kohler’s website, the specifications for this set say the you need the K-301-K and do not mention the K-300-K. Can the set be used with the K-300-K? And How?  Thanks, Bill”

Here is my response to Bill’s question:  “Hello Bill, Great question! Both the Kohler K-300 & Kohler K-301 are identical OD dimensions, but they have different inlet sizes.   The 300 is 1/2″ inlet and the 301 has 3/4″ inlets. 12 +/- years ago 1/2″ was standard for all tub fillers.   Then Kohler came out with the “3/4″ High Flow” valve that can be used on any filler.   However the faucet series you are looking at is Neuville and it is in what Kohler classifies as their “Premier Faucet”. So to answer your question in a long way, Kohler only promotes the Premier Series using “3/4″ High-Flow Ceramic Valve System”.   But I’ve been doing this for 25 years and Kohler used to promote both the K-300 & K-301 for every filler.

They will both work for any Kohler faucet trimAny non-vitreous china toilet components, with the exception of the seat. Examples include the ballcockThe mechanism that controls the flow of water into a gravity-operated toilet tank. The ballcock is controlled by the float mechanism floating in the water in the tank. When the toilet is flushed, the float drops and opens the ballcock, allowing water to enter the tank and/or bowlA water-containing receptor that receives liquid and solid body waste; two general bowl classifications are round-front and elongated.. The float rises as the water level in the tank is restored, and shuts off the ballcock when the tank is completely filled. Also referred to as a float valve., bolt caps and trip lever..  Consider this to help you make a selection decision for the valve system that best fits your needs.  1.  How often will you use the Bath/Whirlpool?  2.  How big is the Bath/Whirlpool?   3.  How many gallons of water are recommended to fill the Bath/Whirlpool?  4.  What is the psi of the water coming into valve system.   These questions should allow you to estimate the time it will take to fill your Bath/Whirlpool?    If you have anymore questions call me at: 888-285-1203. Thank you, Allen”

The big difference between the two valves is how fast you want your Bath/Whirlpool to fill and how much you want to spend on your valve.  I’ve created a table below to help simplify the differences.  Let me know if you have any questions or leave a comment.