You are downloading the Battery Saver 8.1 XAP file v184.108.40.206 for Windows Phone. Battery Saver 8.1 is a free and useful Productivity app: Battery Saver 8.1 is powerful and easiest battery manager app, exclusively designed and developed for Windows phone 8.1 devices to extend battery ... You can now download the offline XAP file to install & try it.
Download Locations for Battery Saver 8.1 220.127.116.11 XAP file
Important Notice: Now Due To Unspecified Limitations, You Can Not Use The Offline XAP File To Install It Any More.
To try to install it manually from an SD card, you should choose one of the server location above to get the offline Battery Saver 8.1 XAP file, move the file to your phone's SD card and then tap 'Install local apps' in the phone's App list.