This is a band used to connect mattresses and prevent them from separating. Mattress Band for 2 Beds - Prevents Slipping, Gap Filling - Belt to Secure Mattresses - Mattress Belt - Otomesan [Advertised in Hiyoko Club] - Otomesan - Family Size - Supports up to Double + Double Size - MB002 Suitable for mattresses up to the size of two double mattresses. Please adjust to your needs. One size fits up to three single (97cm wide) mattresses. [Size] Width 5cm x Length 1000cm, Thickness approx. 1mm *Only one size available. [Material] 100% Polyester [Color] Gray: Both buckle and belt are gray. Convenient to use with a gap pad. I accidentally purchased this and have never opened the box. It is new and unused.