I wish to express my thanks to you for making the best wheelchairs for growing, active kiddos. Both my adopted sons with spina bifida are TiLite users. They used TiLite chairs before their mom and dad. One chair is a YRa with a backup, one demo one new. Other chair that younger son uses is a Twist. Both have been reliable under everything outdoorsy young boys can give them. One set of tires and minor normal maintenance is all we have ever had to do with the oldest of the 3 wheelchairs. Sons taught myself and wife the benefits and engineering and build quality only TiLite gives you. Wife uses a ZRA Series II. My Aero Z Series 2 is being built. Look forward to being a one make fleet. Wheelies to you and highest regard. What we older folks can learn from intelligent youth. Wife and myself also spina bifida.