Usually cars come with one remote... Rarely 2 remotes also come... It depends upon the seller in Japan, how many remotes he/she provide to auction house...
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It is important to keep remote inside the car, otherwise car would stop after some distance, i dont know exactly how much distance, never experienced...
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Another thing if u mistakenly leave remote inside car, car will not be locked with thumb sensors...
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All JDMs doesn't come with immobilizer