Cylinder screws with slot ISO 1207-brass nickel-plated M2,5x16 mm

Slotted screw drives are the oldest form of rotary drives for fastening screws. The Schltz is usually manufactured in a pressed or milled version. Because of its uneconomical processing method (slow, unwieldy), the slot is increasingly disappearing in favor of other drives (hexagon socket, cross slot, hexagon socket).

Brass is a copper-zinc alloy containing at least 50 per cent copper by mass and up to 45 per cent zinc. Other metals are added to impart specific properties to wrought and cast alloys. Brass is wear-resistant, corrosion-resistant, easily formed both hot and cold, and can be polished. Wrought alloys are used in deep-drawn parts, screws, springs, tubes and instrument components, whilst cast alloys are used in valve bodies, plain bearings and precision engineering components.

Nickel coatings are produced either by electroplating in accordance with DIN EN ISO 4526 or by chemical processes in accordance with DIN EN ISO 4527. In the case of electroplating, there is a risk of hydrogen embrittlement in fasteners with a hardness exceeding 390 HV. This necessitates specific measures (such as annealing), although these do not provide a 100 per cent guarantee against embrittlement.