FREETOO Portable Digital Luggage Scale is a must for people whofrequently travel by plane or train. Having it in hand means you knowhow much your luggage weighs in advance so that you can avoid theunnecessary repacking or even expensive extra fees, which usually amountto more than you pay for the tickets in the first place. 1. Unit weight Button Click the unit button to convert weight units(lb, g, ounce, kg) 2. Tare/Zero function If you want to know the net weight, weigh the container first likewise. When the reading is stable, click the button once for tare function. When the reading turns into zero, put the subject in, the reading in stable state show its net weight. Click the power button once to turn it on and several more times to choose your preferred weight unit;Attach the strap or hook to a handle on the luggage and lift it by holding the scale;Read the weight on the digital display when it's stable NOTE Remove the insulating piece from the battery in the first use.This scale can not weigh stuff over 50 kg.Suggest single hand operation for 0-15kgs light weight. Suggest both hands operation for 15-50kgs heavy weight Auto Power-Off, so you no longer have to fret over wasted energy. Tare Function allows you to read the net weight of your luggage easily and precisely. Lock Weight - Once the reading is stable, display locks onto weight for easy reading. Low battery indicator gives you notice to ensure your scale is ready when you need it. Easy-to-read LCD display with backlit is readable even in darkness.User friendly regardless of what measurement system you use. Unit Button for Easy Operation: Easy to weight