Bridgestone has announced the compound allocations of for a further four rounds of the 2010 FIA Formula One World Championship.

Notifications of the compounds to be brought to the Chinese, Spanish, Monaco and Turkish Grands Prix have been made to the teams. The concept of leaving a compound step between the two allocated dry tyre types for an event is retained for all of these races, including Monaco, where the super soft, and for the first time, the medium compound will be used.

In a change to the previous year's regulations, the number of sets of dry tyres available for each driver at a grand prix changes from seven of each compound to six of the harder 'prime' compound and five of the softer 'option' compound. As last year, there are two distinct temperature working ranges of tyres. The hard and medium have a higher temperature working range than the soft and super soft.

All dry compounds are new for 2010, as are the tyre constructions, including a narrower front tyre. The wet and intermediate tyres have no significant changes apart from the width of the front intermediate tyre, which will now be the same as the new dry front tyre.

The softer compound tyre used at any Grand Prix can be distinguished by the green bands on the edge of the tyre side walls. These show Bridgestone's support of the FIA's Make Cars Green campaign.

Hirohide Hamashima, Bridgestone Head of Motorsport Tyre Development: "Deciding which tyres to bring to a Grand Prix is always a difficult decision, especially as we don't receive advance notification of the exact weather we will see at the race circuit over the three days of running. Tyre performance in Bahrain was good, however we remain vigilant and safety is the overriding concern for us. Shanghai and Barcelona are both quite severe circuits and Istanbul, as we have seen in the past is particularly severe. This is why we are bringing the hardest allocation whilst still leaving a gap in our range between the two compounds. For Monaco this year we will have a gap in the allocation too, which is a change from the two softest compounds which we have brought here previously. We have a harder prime compound for Monaco because of the heavier fuel loads and longer stint lengths that the current rules encourage. We believe this allocation should provide a reasonable and interesting difference between prime and option tyres for this event."