anh falleaf cho em hoi. tren trang web
http://www.robot-electronics.co.uk/s...angers1999.htm thi gia srf05 khoang 12USD 1 con. nhung neu tim kiem tren cac trang khac thi gia co the tu 20-30USD. em dinh dat anh mua may con, nhung ko biet gia ca cu the ntn