Dogtra 3500NCP Notice D'utilisation page 26

"Mild" has 63 stimulation levels: (0) is the lowest and (L63) the
highest. This feature gives the trainer a much wider range in the
power band for highly sensitive dogs. The LCD display will show
(L) along with the intensity level (0-L63) when your unit is in the
"Mild" setting.
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Rheostat Intensity Dial
The Rheostat Intensity Dial is located on the top of the transmitter:
(0) being the lowest level and (127) being the highest while in the
Regular Mode.
While in the Mild Mode, your level options will be (0) being the
lowest, and (L63) being the highest. The LCD screen will display
the (L) to indicate that the toggle switch is positioned in the Mild
Mode.
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