Heres that hard to find Unequal size barb splicer you need to connect Vinyl 1/2" flexible tubing to Vinyl 3/8" flexible tubing. Steps up or down. Works with Silicone and Poly tubing. Durable to last years. Made from high standard 304 stainless steel. Commonly used to connect lines of unequal size for low pressure air, water, fuel, oil and inert gases in a quick and simple way. Also available in other sizes (See other items). Note that Poly tubing requires a larger splicer.