Two-lever radiation box for two chrome-plated aluminum motors. By pressing the button on the underside of the handle, the engine speed can be raised without the gear engaged - for example, to warm the engine with the required number of revolutions. The X12 safety switch (not included) prevents the engine from starting when the gear is engaged. Cylinders type C2, C7 and C14 are connected directly to the C5 and C16 coupling and a K35 adapter is required.