The downsized version of 
The downsized version of E-Z Drill’s Model 210B On-Grade dowel-bar drill, Model 110B operates on the subgrade and fits in a 3-foot patch. A minimum of 50 cubic feet per minute air source is required to run the totally pneumatic system, which can drill holes from 5/8 to 2 inches in diameter to a depth of 12 inches. E-Z Drill’s patented roller bearing feed system eliminates carriage friction during drilling, allowing an operator to drill faster with a smaller drill motor. Dual-purpose guide wheels slide horizontally along the concrete slab and can be flipped down to transport the 170-pound machine.