With its multifunctional capability and efficient USB charging systems, the device supports multiple charging methods, eliminating battery replacements and offering a sustainable solution for frequent users Ideal for jewelry enthusiasts, professional appraisers, and collectors, this gemstones tester serves those who demand and dependable hardness assessment tools for their gemstones collections This USB rechargeable diamonds tester pen provides highly accurate gemstones hardness measurements using advanced technology, ensuring accurate results for various stones without environmental interferences Crafted from ABS, the portable hardness meter features a compact design for easy handling and long lasting use, enhancing its practicality for daily gemstones testing Suitable for versatile scenarios such as home use, jewelry shop inspections, or travel adventures, the portable tester allows quick and hardness checks on diamonds, and other stones, Manufacturer: EXQIOUR