Fowler Full Warranty COAX-2D 2 Dimensional Coaxial Indicator Set, 52-710-025, 6.87" Length, 0.250" Maximum Measuring, 0.0005" Graduation Interval 1 year warranty offered by Fowler High Precision Two-dimensional coaxial indicator can be used at any angle for accurate centering and positioning of components in most machining applications 1.6" diameter continuous dial has a 0-50 dial reading, 0.250" offset axis measuring range, and 0.0005" graduations for taking direct readings Three internal and three external feelers and a center point feeler have 1/8" ball diameter, a locating accuracy of + or - 0.0002" of true center and provide a wide measuring capacity of 0-12" (0-300mm), face remains stationary during spindle rotation up to 800 RPMs Set includes coaxial indicator, three internal feelers, three external feelers, center point feeler, restraining arm, and fitted case