Pakistan Electrical Supply System: Wye or Delta 3 Phase?

In Pakistan is our electrical system set up as a 4-wire Wye or 4-wire Delta system? My reading indicates Wye but I am not sure. Can anyone confirm?

Thanks

This would be best confirmed by someone working in the power industry (any KESC employee here? :P ). I'll try to make a logical assessment depending on the basics.

Delta is usually 3-wire, not 4 wire (neutral is not needed). If there is any possibility of using this then it would be for high voltage transmission lines (from grid stations to substation/PMT).

At the substation/PMT (Pole Mounted Transformer) the conversion from Delta to Y takes place & we get 4 wires to our homes (3 for phase & 1 for neutral).

Thanks, I am trying to find a suitable surge suppression system for transient voltage spikes and all of the websites offer 3 phase units in either Wye (Y) or Delta setups, and I couldn't figure it out...

On a side note, surge suppression systems are EXPENSIVE, anyone ever install one here in residential or commercial setting? I am looking at "shunt" setups as opposed to series connected systems which seem to be insanely priced =)