Just got mine back in. AGAIN... I use metric: 11mm on the bottom one, 14mm on the top one closest to M/C, and 12mm on the top one closest to fender. A 17mm to hold the "Block" or whatever its called, was helpful the first time removing. Use a quality wrench. If you strip or round off the flare nuts, life will be unhappy for you....So use a GOOD QUALITY WRENCH or set of "Flare Nut Wrenches" (They are "box ends" with just enough "open end" cut out to fit onto the line)