The ProScale LC-300 comes calibrated and ready to use with 2 AAA batteries. The blue backlit display makes using this ProScale digital scale in your reptile room easy, especially in low light settings. Use the tare function when using a container when weighing your geckos, lizards, snakes, or other reptile pets for an accurate weight down to .01 gram. The VibraKill technology will keep the reading accurate and stable when weighing your animals that might not stay still enough for other scales to give such a precise measurement as the LC-300. This scale is small enough to fit in your pocket and is equipped with a protective cover to keep it safe and stay calibrated longer. The protective cover can also be used as an expansion tray if you need a larger surface to weigh stuff on - just tare the cover and it's ready to go.