CE Certified Steel Reel Water Level Meters or Ground Water Dip Meters.
Various dip lengths available such as:
300m
400m
500m
600m
700m
 
Industrial metal frame construction with a Steel Reel. 9-volt battery used to power the unit. Simple on/off switch located on the side near the battery compartment cover. Simple voltage display screen. Padded carry handle. PE, PU coating.
14/16mm diameter stainless probe with audible alarm.  Simple to read measuring tape.
Simple, cost-effective solution.