This seat covers the seating surface, so there are no gaps in the bottom, making it safe. I purchased this, but with the purchase of an electric bicycle, I haven't used the double stroller as often, and it's been stored at home, so I'd like to sell it. The following information is from the creator: Please refer to it. ------------------------------------------------ Front = Quilted fabric Back = Oxford fabric Fabric color = Black Belts = Black x Gray (Image 1) It's a sturdy fabric. We've used it for 2-Seater for 2-3 years without any problems. It's essential for naps. As this is a handmade item, There may be slight misalignments and loose stitching. Please refrain from purchasing if you are sensitive to these details. *We are not responsible for any accidents. 2 Seater Rear Seat Double Stroller KATOJI 2-Seater Two Seater Rear Seat Safe, prevents slipping ----------------------------------------------