Inner Tube 2.50/2.75 - 19 TR4 Straight Valve Stem - Fits on 70/100 - 19 Motorcycle Inner Tube 2.50/2.75-19 TR4 Valve Stem* TR4 Valve Stem: Centered, Straight Stem, Round Shape to fit on rims with a round valve base. Fits on these Tube Type Tires: 70/100 - 19 Heavy duty durable valve stem. Unbeatable performance and value.