Size 12 inch wheels: Suitable for young children who are just learning to balance and pedal.
Training wheels (might be included): These can be helpful for young children who are still mastering balance.
Lightweight frame (possible): Makes the bike easier for young children to maneuver.
Simple design (possible): Easier for young children to handle and less intimidating than bikes with many gears or complex features.
Bright colors (possible): Can make the bike more appealing to young children.