DoLittle crossbar bike seat for sale, great condition, always stored inside, all original parts included. Originally cost a bit over $100 shipped. The website says it fits most standard frames and kids 18 months to 7+ years. Our daughter rode on another crossbar seat and then this one from early 2-7, though she was definitely getting big for it at 7. This one was far easier and stronger than the other we tried. The crossbar seat is great for littles because you can chat with your kid easily while you ride and they’re learning to balance with you. Most seats are either so far forward or back it’s hard to talk to your kid, plus they’re a far more passive experience for your kid. This one gives your kid the feeling of actually riding a bike.