An up-armored version of the standard Panzer II tank, used primarily as an armored reconnaissance vehicle. Heavier 80 mm and 50 mm armor was added to the front and sides and rear, respectively, increasing the vehicle's weight by 10 tons. This plating decreased the top speed to a maximum of 31 km/h from 40 km/h. It was primarily used by the 12th Panzer Division on the Eastern Front, where it went toe-to-toe with Soviet T-34s alongside Panzer IIIs and IVs.
Credit to Davidman (on Flickr) for the numbers.