SHS Ball Bearing Aluminum Piston Head

Great piston head! Works great! Only problems I have noticed with them is one small machining issue with the vent holes not being drilled down enough to actually be holes, but instead just little craters (I have only ran into this once). Also the fact that they are aluminum makes it easier to strip out if you aren't careful and you overtighten. But in general they are great, and for the price you can't beat them.