If you want to replace the canvas of your parasol, please check if the parasol is a Tradewinds parasol.
You will find the name on the metal tag on the hub (moving part of the parasol that connects the struts).
If Tradewinds is mentioned, the canvas normally can be replaced.
Then also check the size. The size is indicated on a label at the edge of the canvas.

When you click on the parasol, a matching base will be suggested.
If you only want to order a base, please take into account that the base has to have enough weight to support your parasol.
Parasols of 4m oct, 3,5m square and 2.8m square need a base of 65 kg.
Parasols of 2.2m square, 3,2m oct need a base of 45 kg.
Also check the pole diameter of your parasol.

Which size to choose depends on the shaded area you require.