This is a galvanised locknut.\r\nThis galvanised locknut is measured at 20mm.\r\nThese locknuts will be ideal for insuring that bolts do not come free.\r\nLocknuts work by reducing the chance of loosening under vibrations to the nut and bolt.\r\nIt insure a safe connections and no loose parts within your work.\r\nYou could save money, to do so just buy 10 or more 20mm galvanised locknuts and start saving money today.\r\nThis 20mm galvanised locknut comes with a one year guarantee, as do all of our products on electricals247.co.uk.