Features:1. Lightweight Headphones: The basic headphones are made of lightweight, durable high impact plastic. And the wire of the headphones measures about 6 feet in length.2. Ear Pads: The headphones feature the wide-screen headband and foam cushioned earmuff, which are comfortable to wear, and they can increase hearing comfort. 3. Built-in Microphone: The microphone with shirt clip can be adjusted to the ideal position to avoid the howling symptom generated when the microphone and the speaker are separated. And the headphones feature the adjustable flexible boom.4. Widely Applicable: The headphones are durable and lightweight, which are perfect for schools, classrooms, and enterprises.5. Wide Compatibility: The headphones feature the polyester film ball drive. And they are Compatible with all sound cards and portable music devices. And the headphones feature the 3.5 mm (mini jack).Specifications:Sensor: 30mm polyester film dome, ferrite magnetImpedance: 25 ohms on each side, +/- 15%Frequency response: 20-20KHzSensitivity: 110dB±3dB at 1kHzEarmuff isolation: 7dB±2dB at 1kHzDistortion: 5%Volume control: noneDouble plug: 3.5mmImpedance: 25 ohms on each sideFrequency range: 20Hz-20K HzSensitivity: 98dB±3dB at 1KHzHeadband: adjustableEar muffs: noise reduction, ABS plastic, durableEar cushion: PVC artificial leatherColor: black and bluePacking List:1 Pair of Headphones