SPEED BUMP SPEED HUMP CAR STOP INSTALLATION INSTRUCTIONS SPEED BUMPS, SPEED HUMPS & END CAPS: Leave 1-83” between speed bumps for drainage and expansion. Product can be cut with a utility knife, if necessary. For more than 4 trips per day with heavy trucks {e.g garbage trucks), or on an incline, install speed bumps using BOTH adhesive and hardware. Always install Speed Humps using both adhesive and hardware. Not designed for speeds over 15 mph. Sweepers must raise brushes before driving over.