These six coupled engines were constructed with a leading Bissel truck similar to the earlier C (B11)class. The engines were designed to burn wood and were fitted with large chimneys containing spark arrestors. Each engine cost £1,588 to construct. They were rated to haul 70 tons up the Main Range to Toowoomba, five tons more than the C (B11) class.

Three engines (19, 21 & 22) were fitted with larger E class tenders to improve their

range. They spent their last days as shunting engines.