M6 30mm CLUTCH HEAD SECURITY SCREWS STAINLESS STEEL ONE WAY ONLY. 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.
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