Adapter comes  as pictured. Lower part is 50.5mm ID. And upper thread size is 54mm , holder has  retaining ring. You get two rings as pictured. Top ring is single threaded. 

Lens ring been used with minor signs of cosmetic use. I don't see anything damaged, it works good.  I would rate it at 8 out of 10.

Shipping is free within USA and $7 worldwide.