Product Abstract: 4:1 reduction contra-angle Product Description 4:1 gear ratio, Internal irrigation system Air pressure?245-392kPa Atomized water pressure?200kPa Atomized air pressure? 200kPa Rotation Speed? 3500-5000r/min Button?type?chuck ? Bur applicable??2.35mm , ?1.60mm Noise ??70dB A complete set warranty for one year,and cartridge,bearing for 6 months.