Stepless Speed Adjustment: Easily adjust winding speed with a simple rotary knob. Adjustable Winding Tightness: Customize the density of your yarn balls by rotating the tension control knob-clockwise for tighter winding, counterclockwise for looser. Wide Compatibility: Suitable for yarns with a diameter of up to 2mm. Recommended yarn ball weight: ≤200g for optimal performance. Convenient USB Power Supply: Powered via a standard USB interface (compatible with household phone chargers or power banks). No additional batteries required. Compact & Portable: Lightweight and space-saving design for easy storage and use at home or on the go. Product Name: Electric Yarn Winder Input Voltage: DC 5V (USB) Rotation Speed: 250 RPM Max. Yarn Ball Weight: ≤200g Cable Length: 1.1M Product Dimensions: 158 x 90 x 60MM Color: White Material: plastic Package Contents: 1*Electric yarn winder Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.