When choosing a rollator walker for indoors or outdoors to help you with balance issues when walking, or weaknesses of any kind when walking, the first thing you want to determine is where you are planning to use the rollator. Inside or outside of your home? When your goal is to use the rollator for the outdoors, you can choose between knobby tires or semi-flat tires. The knobby tires help you wit uneven terrain like grass or gravel. The semi-slick tires help you on asphalt ground and paved ground. If you have semi slick tires on gravel or grassy areas, it will be harder to push your rollator than with knobby tires. The Trionic Veloped Walker is the largest walker available in the USA. It comes from Sweden and is made to get you back outside for serious walking and muscle build up. A lighter version is the TOPRO Olympos. It also comes with larger wheels that are soft rubber wheels. The Veloped rollator comes with air filled bike tires. If you do find what you are looking for, please let us know and we will find it. Please call us at 877-255 8371. We are here to help!