The product is a 1/4" Union Brass Compression Air Brake DOT Fitting, designed for use in commercial trucks. It is an aftermarket part manufactured with a specific size of 1/4" by 1/4". The union fitting is commonly used in air brake systems to connect brake lines and ensure proper functionality. Made of brass, this fitting is durable and reliable for heavy-duty applications. It is a crucial component for maintaining the integrity and efficiency of a commercial truck's brake system.