The Stabila LD 250 Bluetooth Laser Distancer is easy to use, thanks to its four basic functions for measuring distances up to 50 metres. Ideal for everyone who works indoors and needs to easily document a high volume of measurements. The data is wirelessly transferred via integrated Bluetooth Smart 4.0 technology to your smartphone or tablet. There's no denying this tool will save you an awful lot of time. Specifications: Max. Measuring Range: 50m.Min. Measuring Range: 0.20m.Power: 2 x AAA Batteries (supplied).Accuracy: ± 2.0mm.Laser Class: 2.Output: <1mW.Laser Wave Length: 635nm.