M4 x 25mm One Way Machine Screw in A2 Stainless

One Way Security Screws also known as Clutch Head Security Screws. These screws are designed to only be turned in a clockwise direction so once tightened into position they are difficult to remove (unless you have a specialist removal tool). Can be fitted using a standard slotted screwdriver and ideal for use in applications such as access panels, number plates and many anti-vandalism securing solutions.