Graduations show the inside diameter of any barrel or choke from .22 caliber to 10 gauge. This stainless steel gauge measures 3-1/4" long with a key ring hole. Marked in inches (.22"-.80"), millimeters (5.5-11mm) and gauge (.410 - 10).
The statements and opinions expressed within Customer Reviews reflect each author's personal perspective and do not imply endorsement by MidwayUSA, its Employees or any other organization. Customers should in no way infer that MidwayUSA has validated review information as safe, accurate or appropriate.