Metric Flex Combo Wrench Set. Metric 12-Point Flex-Head Combo Ratchet. Adjustable set screw allows you to set desired head tension. Surface drive reduces fastener rounding providing a better hold. Ratcheting box end needs as little as 5 degrees to move fastener compared to 30 degrees for standard box end wrenches. Flex-Head tilts up to 180 degrees at any interval. Serrated beam allows you to feel which way to pull.