Look at the circled area. Imagine a zip tie underneath that area of the boot. The zip tie secures the boot to the PDK shift. The boot can still move up and down along the shaft (that' what she said), but the tie gives the boot a nice finished "rolled over" look. You secure the shaft to the boot by pulling the bottom of the boot over the PDK knob and attaching the zip tie where the end of the boot meets the shaft,