This was the second batch of GTB 1906 boats. Actually it was the first, but the type ship S138 only joined the fleet in 1908, after the first ships of the V150 class. They were all built on the Schichau shipyards in Elbing and thus all bear the letter S. Compared to earlier models, they are somewhat smaller and only have one 8,8cm gun, but three light 5,2cm guns.