20 PCS 2 in 1 Lipo Battery Low Voltage Tester 1S-8S Buzzer Alarm Description:1. Brand New & High Quality.2. Use for 1-8s Lipl/Li-ion/LiMn/Li-Fe. Voltage detection pricision: 0.01V. Unit voltage display range: 0.5V-4.5V. Total voltage display range: 0.5V-36V. 1S test mode voltage range: 3.7v-30v. Low voltage alarm mode for 2-8S. Alarm set value range: OFF-2.7V-3.7V.3. When the voltage is below the set value,it will buzzer with red LED light,pre-set value 3.3V.4. Push key which can change the voltage settings and save.5. Size: 3.9cm x 2.4cm x 0.9cm.6. For 1S-8S / Lipo / Li-ion / Li Mn / Li-Fe Battery. Features:-This product is using for detecting 1S-8S lithium battery-Detect the voltage of each battery core automatically, support reverse connection protection.-To know the working state of your battery anytime, protect the battery from overcharge and over discharge.-The red LED will flash,the buzzer will beeping when the voltage is below the set point.-The factory default setting is 3.3V, press the button to change the voltage setting, and it will save your current setting automatically. Package Include:20 x Voltage Buzzer Alarm