had my dealer install tints sa car ng wife ko.

ang usapan, 3M BC20 sides and back, BC35 front.

i got the car in the evening so i really could not tell if all was ok. the following morning when i got to look at the car, parang hindi BC20 yung sa backglass. sa tingin ko BC35 yung kinabit kasi hindi ganun ka-mirrorized yung likod. my wife says sa angle lang daw siguro ng salamin. am not convinced kasi with that reasoning. tingin ko nagkamali yung installer. question is how do i show/prove this?