CILOYU Gas Fuel Tank Vent Valve Compatible with Predator 212 196cc 224 301cc 420cc Engine Coleman CT200U BT200X KT196 Mini Bike Gas Pressure Washer Generator Powersports Parts. Function: This fuel tank vent is designed to regulate the flow of fuel tank vapors, preventing the accumulation of pressure within the tank and ensuring that the fuel system operates safely and efficiently.