Rubber Repair Nano-tek is a building in Bloons Monkey City. It costs 2500 and 25 and gives player 200 xp. It is required to research for Regrowth Bloons in the Bloon Research Lab. With it, players can send Regrowth Bloons against other players as well as Regrowth Assaults. The building's animation shows a Regrow Green bloon be popped twice with a small cloud of smoke, then regenerate back to green.