Stens Fuel Caps serve a significant role in maintaining fuel quality and usage for outdoor power equipment. The cap stops liquid fuel and vapors from spilling or being released into the air, and it blocks dirt, dust and moisture from getting into the fuel line and tank. Preventing fuel and vapors from being released helps maximize efficient use of fuel and protects the environment. Stens fuel caps provide a secure and tight seal to keep foreign substances from entering and causing contamination, keeping your fuel system clean and operating efficiently. A tightly fitting fuel cap will also seal in unwanted fuel odors. Stens fuel caps are durably made to resist wear and tear even when frequently removing and reinstalling for fuel refills.