i have visited to the Hyundai Twin city motors Islamabad for engine tuning there a guy checked the plugs, i have DENSO 2 tip plugs so he warn me that these plugs is not for Santro and change it, he give me a suggetion that i can change it with NGK 1 tip, Also he told me that he will change it for free with second hand NGK and will install the DENSO in some other big vehicle so i agree and change the 2 tip DENSO with single tip NGK, now tell me is that fear exchange or he just did a fraud with me? Thank U