HIFROM(TM) Air Filter Element For 150cc Go Kart GY6 Engine Canister Hammerhead 150SS 150GT GTS150 6.000.151. Carter 5133021 1. Hifrom air canister style cleaner for newer Hammerheads with snorkel style air cleaner. 2. Replaces Carter 5133021 and 513-3021 3. Replace Hammerhead 150SS, 150GT and GTS150 Part # 6.000.151. 4. This is not original aftermaket part, but it is high quality replace air filter. Please check the pictures and size carefully before you buy it. 5. HIFROM air filter from OEM BIG Factory; Professional technical support; if you unsatisfy, can return no risk