It is used to detect optical fiber break points and is used in the construction and maintenance of integrated wiring, production and research of optical components and other optical fiber technologies.< br/> Features: Lightweight and portable for easy carrying and comfortable grip. Longer penetration distance, stable performance and long service time. 3 gears adjustable, and there are power indicator lights, pay attention to the power at any time. With convenient LED light for operation in dark environment. Universal 2.5 pen heads mm, detachable, easy to replace the core. Features: Type: B3S05, B3S15, B3S20, B3S30 (optional) Output power: B3S05?: 5?mW B3S15?: 15?mW B3S20?: 20?mW B3S30?: 30?mW Working time: B3S05?: 10 a.m. B3S15?: 3.5?h B3S20?: 5h B3S30?:?5h Interface?: 2.5?mm Output wavelength: 650nm Battery: B3S05?:?2?AAA batteries, 1.5?V, 250?mAh B3S15?: 5?V, 900?mAh B3S20?: 5?V, 900?mAh B3S30?: 5?V, 900?mAh Item size: 125*35*17mm/4.9*1.4*0.7in Item Weight: 56g / 2.0 ounces Package Size: 150 * 60 * 30mm / 5.9 * 2.4 * 1.2inch Package Weight: 83g / 2.9oz Packing List: 1 * Optical Fiber Tester