Bluerock Tools Z1VB is a universal vacuum base and pump for concrete drill stands. Designed to mount your existing concrete core drill stand. We have a separate listing to purchase this base or pump individually. Vacuum Base Specifications: Platform dimensions: 17" x 15" x 2.5" Overall height: 5.5" Mounting stud height 3" Center mounting bolt to the edge of the base: 6.25" (consider this measurement to allow for large diameter coring bit clearance and your core drill stands anchoring point in relation to the edge of your coring bit) Vacuum Pump Specifications: Speed: 1 L/S Rated Voltage: 110V Rated Frequency: 60Hz Rated Power: 1/6 HP Pressure: 1.5X10^4 PA RPM: 3350 RPM Vacuum bases are not designed to work in every environment or application. Very rough surfaces, cracks or very uneven surfaces will reduce suction. Optimal adhesion is achieved on smooth and flat concrete with a strong vacuum pump. The core drill & core bit shown in photos is not included but can be purchased separately.