Feature:* brand new excessive quality*Easy to put in and save space*Sturdy metallic material, coating, not easy to rust, waterproof*They are designed to be screwed into the headboard and foot board of the bed body to carry the centre beam in place.Specification:*Material: stainless steel*Colour: Black,*Size options: clip 50mm, clip 32mm, clip 35mm,clip 40mmPackage Contents:1 pair of mattress connecting connectorNote:1. Due to many factors reminiscent of exhibit brightness and lightweight brightness, the particular shade of the thing may be barely varied from the picture displayed at the website.2. Please allow slight manual size deviation in the data.