One comment. Giant is an Asian company and Shimano is Japanese. The only way your bike could have been "Hand built in Holland" is if that means a local bike shop unpacked it from the shipping box and did the final adjustments.
You will need a 15 mm open end wrench or, if the wrench flats are too narrow, a special thinner 15 mm pedal wrench, to remove the old pedals and install the new ones. The right pedal has conventional right-hand threads. The left pedal has the opposite (left-hand) threading so pedals are side-specific.