Foam tubes and cylinders for penis extender

My penis extender came with a couple of foam tubes and a couple of foam cylinders. I can’t understand their purpose.

The large ones slide over the glans to cushion shaft while using strap or solid tube. Small one slides over solid tube for same purpose. Are these the type foam sets you have?

The product is the Easymax Penis / 24K Gold Penis which is sold by LeLuv.

The foam cylinders seem too small to fit over a penis, so I tried sliding one of them over the strap. They inside diameter is about the size of a ballpoint pen. I suppose it might stretch, but I wasn’t brave enough to try it. They also have solid foam cylinders. Maybe those are the cores that came out of the tubes. There are two foam tubes that seem to be identical.

I’m even more frustrated today, because one of the shafts unscrewed from the hinge on the base, so the hinge fell out. I have no idea where it went. So now it is useless unless I can find that thing.

These things are confusing, and the instructions were pretty vague.