USED ZELLWEGER ANALYTICS MULTI 4 GAS DETECTOR LUMIDOR. APROX 3 YEARS OLD. WAS TOLD IT WAS WORKING WHEN LAST USED. I JUST PUT IN 4 NEW BATTERIES AND TURNED IT ON. SHOWED OUR O2 AT 20.01 %. I REALLY DONT KNOW ANYTHING ABOUT THESE BUT WILL TRY TO ANSWER WHAT I CAN. HAS 2 ATTACHMENTS YOU CAN SEE IN THE PHOTOS.
