Jack Pads
Jack Pads simply fit on to the Corner Steadies. This ensures that you have a nice solid base for the Corner Steadies to sit on, especially when the Caravan is pitched on grass or loose gravel. With the Jack Pads loosely fitted to the Corner Steadies they can therefore sit on uneven surfaces creating a rigid base. 
This reduces the risk of the Corner Steadies from sinking into the ground and keeps the Caravan stable. Most Jack Pads are assembled from a type of strong plastic that can withstand the rigors of having heavy weights applied to them, even on sharp gravel. They are usually supplied in a pack similar to the image here and only take a few minutes to install without the need for any tools. A set of Jack Pads can be purchased for less that five pounds. If you regularly pitch the Caravan on a non solid surface, this will save having to use other items like small pieces of solid wood which have to be put down, taken up and stored every time that the Caravan is moved. With Jack Pads they are fixed to the Corner Steadies and already in place when you need to pitch the Caravan. They are also very light.
Installation
Most installations are very quick and require the use of no tools. It will usually take you longer to raise and lower the Corner Steadies than the time it takes to actually fit them. The set pictured on this page are simply held in place by a pin that pushes through the Jack Pads and the Corner Steadies. With a couple of raised edges the pin can be pushed through the Jack Pad where there is enough resistance with it to stop it from falling out.
Some Jack Pads may need to be installed differently to the ones shown here. Always read the instructions properly to reduce the risk of either losing them when towing the Caravan, damaging the Caravan or Jack Pads.
When using Jack Pads on a non solid surface there will be a small element of subsidence over a period of time. It is advisable to check the Corner Steadies at least once after 24 hours.