Counter-Pen is a combination marker and digital counter designed for the lab and plant. Each time a black mark is made with the felt-tipped pen, it automatically sounds a beep, and LCD displays the counts. Use it to count cell growth on petri dishes, inventory parts, and tally samples received. Touch, sound, and count occur simultaneously. Impossible to make an error, even when interrupted marks hold your place and counter holds your total. Durable ABS plastic unit provides audio/visual counts to 99999 with reset button, on/off switch, and pen cap. Size is 6" length by 2/3" diameter and weight is 1 ounce.