Vernier Ball Micrometer ensures that you can measure this critical dimension with accuracy. Each Hornady Vernier Ball Micrometer has the capability to measure case-neck thickness with an accuracy of 0.0001 of an inch and can measure diameters up to an inch wide. The device includes a ratchet stop that ensures users can place constant pressure on the case for repeatable measurement. A spindle lock ensures that the measurement is preserved after taking the micrometer off the case. The Vernier Ball Micrometer is constructed on a durable C-frame and features a protective finish consisting of baked enamel. Each micrometer ships with a durable, plastic storage case.