We supply functional screw connections such as throttle check valves (either exhaust-controlling or supply-air-controlling), check valves and unlockable check valves in nickel-plated brass for increased mechanical stress. The throttle check valves are suitable for adjustment of the speed of pneumatic cylinders or other pneumatic actuators. An exhaust-controlling throttle check valve is used for speed adjustment of most double-acting cylinders. In this manner, the ugly slip-stick effect is avoided effectively. Supply-air-controlling throttle check valves are mostly used with single-acting cylinders or cylinders with only a very small stroke volume.