Fitting Instructions can be downloaded here – fitting instructions
Please take extra care over those instructions on the diagram highlighted in yellow – the top screw in the upper assembly should be touching the seat stay tube and the lower screw in the lower assembly should be touching the underside of the chainstay tube (use rubber sleeves provided to prevent chafing of the frame).
This video may help a little.
Below you can find the parts provided for Large Adjustabilisers.
Standard Adjustabilisers are similar except that the L-bars are shorter, there is no spacer nut on the wheel support and the wheel support screws are slotted rather than hexagon headed.