13 © 2018 unitech Electronics Co., Ltd. All rights reserved.unitech is a registered trademark of unitech Electronics Co., Ltd.PA720+ User’sManual5. To tighten the two knobs on thebattery cover by turning clockwise.NOTE: After installing the battery, make sure the battery cover is securely closed, or you maybe unable to turn ON the terminal.WARNING! There is a risk of fire and burns if the battery pack is handled improperly. DONOT disassemble, crush, puncture, short external contacts, or dispose thebattery pack in fire or water. DO NOT attempt to open or service the battery pack.Dispose of used batteries according to local recycling guidelines in your area.