Genuine Malossi velocity stack that fits PHF 30-36mm carbs. These shorter screw on stacks were used on lots of Italian bikes in the 1970's. Made of Polished Aluminum with screens to keep large rocks and low flying birds out. Stacks are 45mm long and 65mm wide at the big end. The PHF 30-36mm stacks have 48mm threads and !! SOLD EACH !!