Prokit's Industries NT-6580 - Manual (Page 5)

Display Backlight
Press to switch on or off the display backlight. User can trigger the
function when he/she is in dark situation. The value is clearly visible on
the display.
Distance Unit Setup
Long press to change the distance unit between m, ft, in, ft+/in. Long
press again to continuously change the next unit.
Clear/Cancel
When measuring or calculating, user can press to cancel the last
action, until all data on display are cleared and go back to single distance
measurement interface.
Historical Data
Press to view historical data, including 50 measured and calculated
results, shown in reversed order.
Press to go up to view previous record.
Press to go down to view next record.
Press to go back to single distance measurement interface.
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