Tool Compatibility Working Current ≤ 10 mA (Emitter), ≤ 30 mA (Receiver) Signal Transmission Format Multi-frequency impulse Signal Output Electric Status 8 Vp-p Signal Transmission Distance ≥ 3 km General Dimension Emitter: 126x49x34 mm (LxWxH) Receiver: 175x42x27 mm (LxWxH) Net Weight Emitter: 60 g Receiver: 72 g Gross Weight 335 g (color box) Package List 1x Emitter 1x Receiver 1x Earphone 1x RJ11 telephone Cable 1x RJ45 Cable, 1x Cable with RJ11 Connector & Alligator Clip, 1x User Manual, All above items are packaged in a tool bag.