Re-route fuel from the fuel filter housing directly into the CP3 pump. Eliminates the restriction of the factory fuel test-port / fuel block. Larger diameter allows for an increased flow to the CP3 injection pump. 2001 - 2010 GM 6.6L Duramax diesel kit includes: ? Inlet fitting (see above 1130605) ? 24” 3/8” line ? 3/8” to 1/2” adapterRecommended for single CP3 and Dual Fueler installs where additional flow is needed.