A sequential blow off valve differs considerably from other blow off valves, as it is designed as a pull off valve. It never leaks because it is designed to only release pressure when there is a difference between the two chambers. This is both a smaller valve and it is considerably faster reacting than its counterpart. This value has two parts to it, the quick acting, primary valve and a larger one if further discharge is required. The sequential blow off valve is made of aluminum, which means it has a long life and it has a high shine finish. You can buy it in a kit form, especially for your make of vehicle, or you can purchase a universal kit.
For more info, see Installing an HKS SSQV Blow Off Valve