The IN-2 is the Soviet equivalent of tiny American tubes like the Burroughs 4021. The digit height on the IN-2 is 10mm and the envelope diameter is 17mm, which makes it slightly larger than a 4021. The IN-2 has a high domed front and a side nipple that exits the tube at a 45 degree angle to the digit, for for side-by-side mounting in multiple tube displays. The print on the side of the tube is covered with a resinous coating, which protects the print from being wiped off by the person installing the tube. The main drawback of the tube is its tiny base, the socket for the tube is rather hard to find, and the pin spacing is very narrow, making attachment of leads difficult. It should be noted that while it is common to blindly refer to all Soviet tubes as being manufactured by 'Sovtek', the example shown here was actually manufactured by Anod.