Clear Vinyl Tubing - (ID) 1/4X - (OD) 3/8X - 1000 ft Made from strong and durable vinyl material, these tubes are available in a variety of sizes and lengths, great for use with air or water. The tube walls are thick and flexible, and you may choose between the 100% opaque black vinyl, which prevents algae growth, or the clear vinyl that allow for complete visibility. Inner Dimensions: 1/4'' Outer Dimensions: 3/8''