The technical specification for 35kV transformer includes: 

• Off-circuit Tap Switch (OCTS) or Onload Tap changer (OLTC) with a tapping range of ± 2.5% to ± 5% (OCTS) and + 5% to – 15% (OLTC) 

•The terminations may either be HV Outdoor Bushings / LV Outdoor Bushings or alternatively HV and LV Cable Boxes (only up to 36kV) 

• The tank construction may be free Breathing with Welded Lids or Flat under Base or alternatively Skid Base