Drummond, for example, had abandoned the round belt in 1921 and changed to an inch-wide flat, an option denied to Exeter Engineering by the compact nature of their drive system.

• 德拉蒙德，例如，已经放弃了轮带，在1921年改为1厘米宽的平面，一个选项否认到埃克塞特工程的性质，其紧凑的驱动系统。