1、Low Noise: The electric pencil eraser has a noise reduction design, low noise will not disturb your study 2、Large Capacity Charging: The electric eraser is a large capacity charging model, charging for 3 hours, usable for 30 days, 20 times a day, 9 seconds each time, usable for 30 days 3、2 Refills: The rechargeable electric erasers have two kinds of refills, thick core eraser for daily study and fine core eraser for painting 4、Plastic Collet: The electric drawing eraser comes with a low temperature plastic collet, which is not hot enough to handle 5、Non Slip Design: The electric eraser has a red button non slip design, suitable for small children to grasp, press, and wipe back and forth with a light press Item Type: Electric Eraser Material: ABS, TPR Function: Sketching, Painting, Industrial Design Battery Type: Lithium Battery(shipped with built in battery) Battery Model: 14500 Battery Capacity: 800mAh Coarse Core Rubber: Daily Learning Thin Core Eraser: for Painting, for Highlighting, for Detailing Charging: Red Light when Charging, Green Light when Fully Charged, Blue Light when Working Product Size: Approx. 2.7 x 16cm / 1.1 x 6.3in 1 x Electric Eraser 1 x USB Cable 1 x Sticker 1 x Rubber Sleeve Clip 16 x Thin Erasers ( with 6pcs in the Product) 12 x Thick Erasers (with 2pcs in the Product)