An underbody car wash sprayer for home-use, which can be hooked up solely to a garden hose or in combination with a pressure washer. Requests for dynamic content are forwarded directly to a content server to avoid caching data that might only be used once. This method involves providing boron nitride powder and milling the boron nitride powder in a mixture including a milling media and a milling liquid under conditions effective to produce delaminated boron nitride powder.