David White 3900HV Owner's Manual page 15

The detector aids in locating and targeting a visible or invisible beam emitted by
a rotary laser instrument; perfect for use in outdoor conditions, where sunlight
and distance may make locating the beam more difficult.
The laser detector includes a rod clamp which allows to mount the detector
onto square, round or oval sighting rods.
b
a
c
d
e
g f
LD20 DETECTOR
LD20 FEATURES
10
LD20
2
1
8
7
3
4
5
6
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