28mm rotary hammer: CE approval quality, 1050w powerful, Efficient and for long time constant work, 24 hours per day service rotary hammer Max drill diameter:28mmRated voltage:220/110vRated frequency:50/60hzRated input power : 1050w No-load speed:800rpm Efficient and for long time constant workDouble insulationCarbon brush quick change.Any questions, please feel free to contact us!