What must you remember when you see this traffic sign?

This traffic sign mandates the use of snow chains on your tires in snowy or icy conditions. It is a circular blue sign with a tire wrapped in chains, indicating a legal requirement rather than a recommendation.

The first point, "Use snow-chains," is correct because the sign directly requires snow chains to improve traction and safety on slippery roads.

The second point, "Maximum permissible speed 50 km/h," is often associated with snow chain usage. When using chains, you must not exceed this speed to prevent damage to the chains and ensure safe driving.

The third point, "Track-vehicles have priority," is unrelated to this sign and not part of the instruction it gives.

So, when you see this sign, you must fit snow chains and adhere to the speed limit, typically 50 km/h, for safe and lawful driving under winter conditions.