It comes  as pictured, adapter is complete with retaining ring. Lower part is 37mm OD.  Retaining ring is 44mm OD , series 6. 

Lens ring been used with minor signs of cosmetic use. I don't see anything damaged, it works good. So you get two rings.  I would rate it at 9 out of 10.

Shipping is free within USA and $10 worldwide.