Closed-circuit hydraulic brake, designed for ISO 15552 cylinders. Consists of an oil-filled cylinder, flow control valves, and a compensation reservoir. Available in Ø40 and Ø63, with extension, retraction, or dual stroke adjustment, plus SKIP (slow/fast) or STOP valves. Periodic oil refill (DEXRON ATF) is required, indicated by the oil level dipstick.