Sanwa KDP10 Instruction Manual page 12

Make sure that the power is turned OFF before replacing the battery.
"4-3 Checking ON/OFF of the Power"
1) Push the knob on both sides of the battery holder to pull
out the battery holder, then remove two coin batteries.
* Pull out the battery holder with the product upside down.
Otherwise, the batteries will fall.
Knob
Battery
holder
2) Get two new batteries ready, check the polarity and
mount them into the battery holder.
* Recommended battery: LR44 (alkali-coin battery) 1.5 V × 2
3) Insert back the battery holder until you hear a click sound.
WARNING
Knob
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