This replacement 2-PT. chin strap is listed for SC-6, SENTRY III and CHARGER hard hats. It is a chin strap accessory for hard hats and safety helmets. Before ordering, confirm the configuration and task requirements for the hard hat or safety helmet in use. Check the equipment identification against the models named in the product title, and confirm that a replacement chin strap is the accessory required. The supplied information identifies the accessory type and listed hard hat models but does not provide further configuration details. Use those details as the starting point for product selection, and resolve any outstanding fit or application questions before placing an order.