A device for testing a battery, particularly a small, portable battery, comprising a flexible, transparent substrate on which is deposited {TAIL ~ a narrow band} of {HEAD ~ a black light} absorbing material 
A device for testing a battery , particularly a small , portable battery , comprising a flexible , transparent substrate on which is deposited { TAIL ~ a narrow band } of { HEAD ~ a black light } absorbing material
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH