Picotest M3500A Service Manual page 19

[Step 1]
Turn off the multimeter and disconnect the power line cord as shown in
Figure 2-19. Also, you should remove all the test leads that connected to
your instrument.
[Step 2]
Please use a flat-blade screwdriver with a suitable pushing strength to turn
it left for releasing the holder.
Figure 2-18
Figure 2-19
19