Motor to countershaft and countershaft to headstock belts of the NuT-Link Type in a Z-Section.  Link belts help to reduce the vibration normally passed from a single-phase motor to the lathe - and was a fitting often used by Myford Service engineers to "quieten" a noisy machine. On the Super 7 and ML7R, the T-link belt is highly effective on the drive from motor to countershaft.
On the drive from countershaft to the main spindle, it is often the case that there is insufficient room between the inner face of the headstock and the largest pulley on the spindle -this meaning that the very lowest speed is not available. In order to use a link belt that gives the lowest speed, a length of PowerTwist belt can be used - and can be found here.
Select your required belt - motor to countershaft or countershaft to headstock - below: