Power : 18 VPerformance: Concrete : 20mm /Steel : 13mm/ Wood: 26mm. Blows per minute: 0-4000 bpm. Weight: 3.5 kg / 7.7 lb. All buyers have the right to return the item if not satisfied. We will do the best to solve the problem that may occur.Please send us a message if you have a problem on items. Before opening a case or leaving feedback we will do our best to resolve the problem.