Genuine Malossi velocity stacks that fit PHF & PHM 30-42mm carbs. These 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 70mm long and 65mm wide at the big end. Please select the size you need from the pull down menu. !! SOLD EACH !!