Schumacher Yellow Rallyblocks.
These tyres offer a little less grip than the White compound but offer a much better wear rate and will typically last 2 or 3 times longer than the whites. They are often used as the tyre of choice on very high bite carpet and astro turf where a little less grip is welcomed.
The rally block tyres work on a wide range of surfaces, they give good grip on carpet, astro turf, wood, lino and gym floor.
For the best wheel / tyre / insert combination see the following links.