This is a simple Beach Umbrella Tip replacement part for a 22.5mm inner diameter pole.

There are two tips on offer here.

The first is a snug fit, it may need to be glued into place.

The mk2 version is 23.mm diameter and will need to be hammered into place using a Rubber Mallet. In doing so the Umbrella tube will strip away some of the wall of the part ensuring a solid interference fit that will not pull out easily.

I do suggest using a minimum of 3 Walls to give the tip some strength against wear and tear of being driven into the ground (sand or soil). It is only plastic so stay away from shingle, stony ground, that kind of stuff.