If you want an easy way to balance your beer lines, this is the way to do it. One of the benefits of Flow Control disconnects is you don't need to rely on the small ID or line length to apply flow resistance. Rather than adjusting your line length or size, simply apply additional restriction directly on the Quick Disconnect (QD). This is perfect for people who want to serve a large range of beverages with differing carbonation levels without having to customize each line. Now with the added benefit of Duotight fittings built in.

Please be aware that even in the fully open position these FC disconnects do have some inherent flow resistance so you should use either shorter line or larger ID line that you would when compared with traditional ball lock disconnects.  

Flow Control QD vs. Flow Control Faucet
One of the only drawbacks of flow control devices is that they inherently create a small amount of turbulence and therefore can cause foaming. In the past, flow control faucets have been the only common option. Flow control faucets are very popular but due to the fact that they are placed at the very end of the beer line they have no head pressure. As a result, any turbulence created can cause foaming and carbonation to come out of solution.

Flow control ball lock disconnects like these on the other hand have the ability to restrict the flow before the beer enters the beer line so the head pressure created by the beer line keeps the carbonation in solution. Even in the instance that high turbulence is created the beer will be far more resistant to foaming issues. For this reason, flow control ball lock disconnects like these have significantly better performance allowing you the flexibility to adjust line resistance easily but without the introduction of turbulence that creates foaming. It cannot fix over-carbonated beer, but it can reduce the amount of beer line you would need to pour without excessive foaming.