Economical combination marker and digital counter for bacterial colonies on petri dishes and Petrifilm™. It can also be a useful tool in the plant when used for inventory partsand tally samples received. Sound and count occur simultaneously when black mark is made with the felt-tipped pen and LCD displays the count. Pen marks hold place if interrupted and counter holds total. This ABS plastic item counts to 99,999 and has a reset button and on/off switch. Complete with replaceable pen, cap and battery.