The U-5TS (GRAU designation 2A20) is a Soviet tank gun designed exclusively for the T-62 main battle tank. It is a smoothbore gun, the first of its kind, which allows it to fire high-velocity APFSDS Shot that can penetrate thick armour. It has a rate of fire of 6 to 10 rounds per minute, depending on the skill of the crew. Later versions of this cannon are able to fire ATGMs, which though slower and harder to aim will break through any armour. As far as guns for retrofitting unto older tanks go, the U-5TS stands out as a premium choice even amongst Oceanyka's richest tankers. An upgraded version named the D-68 (GRAU 2A21) exists, optimised for use with the T-64's basket autoloader system.