This kit was designed to clean the gas tube without complete disassembly of the AR rifle. It contains two gas tube brushes and a clear guide tube. This patented technology allows the gas tube to be cleaned easily and to save time without removing it. Apply a little Iosso Triple Action Oil to the Gas Tube Brush. Insert the clear guide tube over the end of the Gas Tube. Hold the brush end of the gas tube brush close to the bristles and slowly feed the brush through with short strokes until it reaches the end. Repeat if necessary. The combination of the Triple Action Oil with the gas tube will remove the built up carbon.FeaturesCleans gas tube without disassembly of rifleWorks for AR-15 and AR-10/LR-308 patterned rifles