hat ruler Measuring cap circumference tool, adult and child 49-62cm

Analyze material, process, and performance Product Use Hat ruler, also known as inner diameter ruler/measuring cap. There are various specifications for hat rulers, Extra large size 57-70cm, enlarged 55-68cm, medium size 49-62cm， Small size of 42-52cm, made of materials other than outer ring and screw The outer material of the wire is stainless steel, and the rest of the material is copper, which is durable and long-lasting/ No rust. Instructions for Use First, place the ruler in the sweatband position of the hat, and then hold the ruler hand The handle expands the steel ring outward to support the sweatband, and at this point, the pointer points to the mark The size on the dial is the size of the hat A is the American standard, CM is the metric system, F is the French standard, E is the British standard, and the most The commonly used unit is the metric system (CM) Precautions 1. Do not store instruments near acidic or alkaline substances 2. Do not wash with water/try to avoid contact with liquids as much as possible 3. Do not let other items squeeze/handle gently When there is an error, the two screws on the pointer should be slightly adjusted 5. When measuring a hat, place the ruler in the hat and gently unfold it for measurement Do not exert excessive force.