Ensuring the proper hose size is used allows your drill to live up to its potential. If the hose is too long or too narrow, it will restrict air pressure, which affects drill speed. In extreme cases, an inadequate hose size will prevent a drill from operating all together. Each drill requires 100 CFM to operate. If you are using a multi-gang drill and suspect you may not be getting enough air, turn off one drill. If the remaining drill speeds up and operates as expected, it means there is not enough CFM to operate all the drills at once. For specific hose diameters and lengths for your particular unit, consult the chart below.