The Ting family of yoyos is POM / Delrin plus titanium rings. They are inexpensive, super durable (I have an “extra” one I spark regularly and it is still glass smooth) and play incredible. The really cool part is that they come in 3 different shapes!
From left to right: H, V, and O. Every time I bring these to yo-yo club meetups people love them… like, a lot!
And there’s now… drum roll… a METAL TING! It’s called the Machination. I just got mine in the mail from @Vivektoybania and look at this special preorder colorway 
I love Vivek’s work here in not just running India’s #1 yo-yo store 
but working hard to create new interesting yo-yos such as the Machination and the slimline delrin Thing – if you can support his work, please do!