Material: The product is made of rubber and brass, which is durable. Easy to install: just put the fastener in the hole, insert it and put it on. tighten it to enlarge the sleeve. Size: 12 x 14 mm (W x H), thread size: M5. Application: Usually used in car shelving systems , kayaks, motorcycle windshields, multifunctional truck equipment, compressors and motors. Package includes: 10 x lock nuts. Features: Marine grade rubber with brass threaded insert. Commonly used in air conditioning systems. automotive upfitting, kayaks, motorcycle windshields, hardware in utility trucks, compressors and engines. Creates a tight seal and minimizes vibration and shock, vibration isolation helps prevent rattling and tearing. Screens Rubber well rouses are a common choice for waterproofing holes where a fixture is needed. Simply place the fastener in the hole, insert and tighten to enlarge the sleeve. Specification: Material: rubber + brass < p>Size: 12x14mm (W x H) Thread: M5 Package includes: < p> 10