Check the listing for details. RG-2 Relay Valve Trailer (Replaces Haldex Midland KN28510 Velvac 34057). Condition: New. Listed at 35.63 USD. This RG-2 Relay Valve Trailer is a top-quality replacement part for your vehicle. It is compatible with a range of brands including Haldex, Midland KN28510, Velvac 34057, and Mack 5396KN28510, and comes with a 1-year warranty for your peace of mind. The valve is designed to meet your vehicle's specific needs and is a reliable choice for any commercial truck owner. With the Other Part Numbers including N30108BL, 34057, EMDKN28510N, 5396KN28510, and more, this relay valve is a great choice for those looking for a custom solution. It is a non-modified item and is suitable for use with a variety of engines and components. Whether you're a professional mechanic or a DIY enthusiast, this RG-2 Relay Valve Trailer is a great choice for your vehicle.