The RCBS 1" Vernier micrometer is a great tool for reloaders wanting to measure the thickness of their brass or measure the wall thickness of other materials quickly and precisely. Specifications: - Type: vernier micrometer - function: measure thickness and uniformity - Accuracy: .0001" - Range: 0-1" - Warranty: RCBS limited Lifetime - Includes: adjustment wrench and fitted plastic case - features: thimble lock for measuring constants - one piece steel frame.