This is a T-shaped perch. Commercially available perches are quickly chewed and become tattered, but this one is made of very hard wood, so it is durable. (Zelkova) It is also safe for cockatiels. We use wood that is safe to eat. No nails or other metal parts are used. It is made to fit the H&C T-shaped perch holder (15mm diameter). Please note that the holder is not included. We cannot accept returns or exchanges, so we appreciate your understanding.