For anyone performing a Coyote swap on a vehicle that has a heater bypass valve, you may find that when the heater is off the valve closes and disrupts circulation in the Coyote Cooling system. This “H” shaped bypass helps circulate coolant when the valve is closed and keeps cooling temps under control. The H bypass is 5/8″ of an inch on all four corners. This product is only needed if you are working with a Heater system that have a control valve that closes when the heater is off.Each Ford heater kit from TD Motion comes with all the necessary components for a hassle-free installation, ensuring that you can quickly enjoy the benefits of improved heating. Our commitment to excellence means that you can trust our products to enhance your driving experience, providing reliable warmth and comfort in any condition. Choose TD Motion for your Ford heater needs and experience the difference that quality craftsmanship and innovation can make.