Find a wide array of Silicone Couplers & Boots to finish your custom intake on your 2004.5-2005 Chevy/GMC 6.6L LLY Duramax. Straight, hump, reducing, and angled couplers ranging in 45 to 90 degree bends are available to fit almost any need. These couplers are constructed with durable rubber or silicone and are reinforced for greater strength. From 2" all the way up to 6" in diameter, you"ll find the coupler to fit your needs. With high-quality brands like PPE, Vibrant, Mishimoto, and Full Send, you"ll find what you need at XDP.