The Radium Engineering charcoal canister purifies odors that emit from the fuel tank vent system. It is designed for both EFI and carbureted fuel systems.  TESTING To test for a restrictive pressure drop through the charcoal canister, a quick flow Radium Engineering dry break dump can was used. Results showed a negligible difference between a charcoal canister installed or not installed on the fuel vent. Fuel vapor measurements were taken with a combustible gas detector which detects 50 ppm to 10,000 ppm.  All probe testing was measured inside the atmopsheric exit of the fuel tank vent. Without the charcoal canister installed, the gas detector maxed out over 10,000 ppm of fuel vapor. With the charcoal canister installed, the gas detector did not measure any fuel vapor (