Does what it's supposed to, achieves higher flow rate. Quality workmanship, cheap effective upgrade.
Not a whole lot to it but it was machined nice, no burs etc. Can't really quantify how much of an improvement if gives your flow-rate but it seems to work fine, a cheap upgrade that can only help. A good addition to a high flow valve that doesn't come with it's own pin like the Turbo Valve, but can also be used with a stock valve. A must for someone striving towards a low pressure setup.
I recomend this product you can't go wrong, cost effective upgrade. Especially if your lookin at upgrading your valve to a Turbo valve.