... 3.Backrest rotation angle:360 DC-I Dental Unit Chair Dental unit chair, dentist's stool, pneumatic sring height control, ... range:120cmBackrest rotation angle:360 DC-II Dental Unit Chair Dental unit chair, dentist's stool, pneumatic sring height control, ... adjustment range:120cmBackrest rotation angle:360DC-III Dental Unit Chair Dental unit chair, dentist's stool, pneumatic sring height control, ...