This is a gel cushion from TITIROBA. I bought it, but it doesn't fit the chair I'm using, so I've only used it a few times and it's been stored at home. The cover is removable, so I've cleaned it at home, and I've wiped the gel mat and dried it in the shade. It's an extra-thick type with a thickness of 4.5cm. 50 x 50 x 4.5cm Thank you for looking.