Isn't it lovely? Don't ask me about the mechanics...all I know is it works great and is smooth and sturdy. I use this swift when I'm making hanks from thrifted yarn; its sturdy construction allows me to quickly dismantle a ball of yarn into a hank I can then wash and dry, like these lovely darlings:
Or I wind them using the ball winder. Unfortunately, because the wooden swift from the hubby is not adjustable, and sometimes the hanks shrink after washing, I bought a cheap plastic umbrella swift to make life easier. It also works for yarn I buy new as hanks like the Cascade Heritage pictured above.
This thing works but I'm not sure how well it will hold up. It feels rather flimsy compared to the wooden version but it is easily adjustable so it makes winding from a hank easy. I did try making hanks using this swift and it sucks. Its ok for lightweight yarn but anything heavier than DK and this baby is bouncing around like crazy. It is adjustable from horizontal to vertical which is nice but I still prefer the wooden version for making hanks.