What all are you trying to do? Let me first off say, any plastic bov will not work properly. Any eBay unit will out shine those ( I know, you are looking for size), also you need to tee into your vac. In the intake For a bov to work properly. The vacuum on the intake opens the bov. A bov that does not work properly will not let go of the charge air, throttle body closes, is a slam of air that has to go some where, which is right back into the turbo. bent fins, blown fins, blown seals bushings and compressor is just a start. I have even seen a turbo (eBay) break in half just because of bov. So, long story short, don't skimp here. Look on clist, there some good deals some times. And my bov is two inchs.