The Greenlee 0134-0500 DigAlert Probe is designed to determine, without a physical connection, if a high-frequency signal is present on a wire pair. It will directly reproduce audio signals such as speech, base-band modems, or fax tones though its primary purpose is to output a distinctive two tone alarm if high-frequency signals (such as data) are present. 

Originally designed to test the network for the presence of digital circuits, the 0134-0500 DigAlert Probe allows technicians to quickly establish in jointing boxes, cabinets, and racks if a pair is active prior to any maintenance action.

Benefits include:

• The only digital probe design known to be "waterproof" to IP67, the DigAlert Probe is encased in a plastic shell with a unique membrane system that allows the product to 'breathe'. The membrane system also prevents the ingress of moisture, caused by pressure changes resulting from variations in temperature.
• The case is designed with strengthening ribs to prevent damage if the probe is accidentally stepped on, and the probe will float if accidentally dropped into deep water.
• The probe has a high output loudspeaker precluding the need for any form of headset.