HAL (LOW) on/off. Press the Laser/Backlight button 
to  turn  on or off. Press the Measurement Trigger  to 
confirm  the  High(Low)alarm  mode.Hal(LOW) 
adjustment. The high(Low) alarm adjustable form   
   -40 to 650
 o
C(-40
  ~ 1202 ) 
The function of TRIG means that when the TRIG is 
turn  on  ,press  and  hold  the  trigger  for  more  than  10 
minutes ,the device will turn off.
 
 
MAX MIN DIF AVG indicate the MAX IN DIF AVG record
that displays between the pressing and releasing of the
“ON/OFF” button each time.