The balls and the harness are both made of silicone. They both have a very soft and smooth feeling. The balls are firm, and have a small internal ball that you can feel bumping around when you're wearing them.
The harness is a little flexible, to allow the balls to fit in it.
The kit could be for either beginners or more advanced users. The material is smooth, and the balls are small enough that most people shouldn't have a problem inserting them.
This kit comes with two balls. One of the balls weighs 30 grams, and the other is 40 grams. There's actually a surprising weight difference. There is also a little harness, to hold the balls in. You can start with the lighter ball, and when you're comfortable with that, you can move on to the heavier ball.
Each ball has a little divot around the middle of it, which is the shape of the harness. So you just line up the shapes, and they fit comfortably together. There's no pinching of the skin or anything like that, which is something I worried about at first.
The harness has a loop on it, which is used to make it easier to remove the ball. It's actually pretty handy.
The balls are about the size of Ping-Pong balls. They're not huge, and could probably be used by beginners.
This could probably be considered discreet, but I'm sure you would get some questions about it. If you didn't have the harness attached, they would be more discreet, but then you may have to worry about kids picking up the colorful balls. Ew!
I'm pretty happy with this kit. I love using kegel balls, and these are probably the nicest ones I own. The silicone is soft and smooth; the loop on the harness is great. They're a decent size. It's all a lovely combination.
My favorite way to use them is while using a clit massager.
You can clean these toys pretty easily. Just use warm water and soap. You can also use toy cleaners or wipes. I keep mine in the original box, but you can pretty much keep them anywhere. Silicone can have a reaction with other silicone toys though, so careful when you store them.
You can use water based lube with these toys.