The product shown is a Ramous gel bike seat cover.
It is made from materials such as high-density foam, silicone, and lycra. 
The seat cover is designed to be anti-slip, shock-absorbing, and comfortable for long rides. 
It is suitable for various types of bicycles, including mountain bikes, road bikes, and indoor spin bikes. 
The cover is easy to install with a drawstring and straps. 
Some versions are waterproof, dust-proof, and washable.