Work-stools have three different ranges for the seat height adjustable according to different sizes and/or heights for working. It can be adjusted with the help of a gas spring operated by a hand lever under the seat. All work-stools are equipped with safety castors keeping the chair in its position when not in use. They are made of highly polished aluminum base part and a chrome-plated column. The massive, chrome-plated foot-ring avoids sagging of the legs. These chairs are also available in an electroconductive version. The seats have a diameter of 36cm or 40 cm. You can also get a seat with an ergonomically shaped conical design in the front part which helps taking away pressure from the surgeon's thighs.