3 working modes: The visual fault locator features 3 working modes: always on, fast flashing, and slow flashing, making optical fiber testing much easier. Universal interface: 2.5mm universal interface, supports FC, SC, ST common interfaces, and the operating wavelength is 650 ± 10nm. Red light source: To ensure longer penetration distance and stable performance, the VFL also has a detachable metal pen tip for easy replacement of the ceramic core. Aluminum alloy: Using premium aluminum alloy material, the pen-type red light test pen is very convenient to carry for outdoor work. Other features: Multiple static protection, with optical port protection device, the operation is very simple, allowing for high efficiency. Item Type: Visual Fault Locator Material: Aluminum alloy Battery: 2 x 1.5V AAA battery, shipped without battery. Application: For optical fiber communication detection. Operating wavelength: 650 ± 10nm 1 x Visual Fault Locator 1 x User Manual Customers are our highest priority. If you discover any issues with your product after receiving it, such as damage or incorrect quantity, please contact us immediately. We strive to provide you with the best after-sales service.