The transparent acoustic tube can fit snugly in your ear, comfortable wearing experience for your ear, and can transfer HD clear sound. Moreover, it's lightweight and easy to conceal, so it's widely used for security at restaurants, hotels, shopping mall and more. Notes: 1. Please note that the product is for listening ONLY. NOT suitable for conversation. 2. It can be used for PC / Mobile / MP3 ,but please be informed that the voice may be lower because of different impedance. 3. Please note that the radio is not included. 4. Please allow slight error due to manual measurement. Thanks for your kind understanding. Features: Acoustic Tube Earpiece - Fits two-way radios (audio only) with 3.5mm M head earphone jack. Air tube protects the body from radiation and reduces noise for more clear sound. Transparent acoustic tube would be hardly noticed by others. The ear-hook is comfortable to wear and not easy to fall. With clip, to avoid sway of the earpiece. Strong and durable, also flexible enough for easy storage. Suitable for patrolmen, guards, ceremonies, restaurants, hotels, and other security personnel. Specification: Type: Acoustic Tube Earpiece Material: PU + ABS Color: Black + Transparent Connector: 3.5mm M Head Cable Length: Approx. 60cm / 23.6in Weight: Approx. 49g / 1.7oz Package size: Approx. 14 * 12 * 2cm / 5.5 * 4.7 * 0.8in Package list: 1 * Acoustic Tube 1 * Elastic Cable 1 * Earbud for Replacement 1 * Clip