Profile: Invo Spline, Inc. offers measuring and test equipments. Our products are precision spline gages, quick check spline gages, indicating type spline gages, pos-a-check spline gages, external gear rolling fixtures and automatic fault detection systems. Our solid-type spine gages for both internal & external checking are manufactured for involute, straight-sided, angular sided and parallel sided splines. Our indicator type rings & plug gages check the same tooth profiles as that of the solid type gages, except that they measure exact tooth or space dimensions to within 0.0001 of an inch using comparison to a master gage of a specific size.