Considering buying a PAS but have to buy it out of state and get it posted. I was wondering what they look like ?. What's the deal with the spring, it costs nearly as much as the screw ?. Are they just a screw with a tapered end and a hole up the centre and out the side or some grooves on the outside diameter to let the air in ?. Does anyone have a noisy slide ?. I guess it is the slide plate but it has a rubber ring on it. Mine sometimes makes a chattery noise at idle. Chucky.