GearWrench Flex-Head Combination Ratcheting Set 7 Pce Metric: 9900Sizes: 10mm, 12mm, 13mm, 14mm, 15mm, 17mm & 19mm. Patented surface drive reduces fastener rounding. Flex head tilts up to 180 degrees at any interval Set screw allows you to set head tension Ratcheting box end needs as little as 5 degree turn to move fastener. Designed for tight spaces. Sleek head design enables access to tight spots where a ratchet will not fit.