This is a volume adjustment extension cord for adding volume control to headphones and earphones. Volume is adjusted with an easy-to-fine-tune dial. The volume is zero at the minimum position. Connector Type: φ3.5mm Stereo Audio 3-pole Male - 3-pole Female Cable Length: Approximately 28cm from tip to tip (manufacturing error ±2cm) Weight: Approximately 8g I purchased this but have kept it in storage without using it. I will ship it within 24 hours.