The size will always be a combination of either 4.10/3.50-4 or 410/350-4 or 3.50-4 or 350-4. The last digit of 4 being the 4" (101mm) wheel rim size. Replaces any 4.10/3.50-4 or 3.50-4 or 4.10-4 or 350x4 or 410x4 or 11x4.00-4 tyre fitted to Mini BMX Bikes.
eBay