[SIZING REMINDER] Please refer to your specific tubing requirements instead of the size chart for the best fit. Use for joining 3/8 fuel and transmission lines. Specifications. Material: Brass SAE or Metric: SAE Thread Diameter: 5/8 - 18 in. Tube Diameter: 3/8 in *Quick to install and easy to use. 4LIFETIMELINES Brass Brake Line Union, 3/16 (M10x1.0 Inverted), 10 Automotive Brake Fittings 10pcs Brake Pipe Nuts Male Metric 12mm X 1.0mm Nut Galvanized Brake Line Fitting Kit For Inverted Bell Mouth Of 3/16 Pipe. - 34 Automotive Brake Repair Fittings [QUICK INSTALLATION] Designed for straightforward installation, these unions allow you to efficiently complete your projects without hassle. Explore a wide range of the best brass brake fittings on to find one that suits you! Besides good quality brands, you’ll also find plenty of discounts when you shop for brass brake fittings during big sales [ANTI- & WEAR RESISTANT] Crafted from brass, these fittings are designed to resist and wear,long-lasting performance in various conditions. Specifications: *Part Name:Brake Line Union *Material:Brass *Size:1/4,5/16,3/8 *Color:As the picture shows *High Universality Fitment::Yes *OEM Number:No *Fitment:Can be used in hydraulic lines, fuel lines or brake lines, Package Content: 10 Pcs*Brake Line Union