The tight and twisty Ricardo Tormo circuit in Valencia hosts the official opening day of the 2011 Formula One season tomorrow and the debut of Pirelli's new PZero tyres, of which four dry types and two wet types will be offered throughout the season.

Testing will get underway at 10:00 tomorrow, marking the beginning of four official sessions before the first Grand Prix of the season in Bahrain on 13 March. Following the Valencia test, which ends on Thursday, the teams then head for Jerez the following week.

The 12 teams had an opportunity to try out Pirelli's soft and medium tyres for the first time last year in Abu Dhabi, just a few days after the season-closing Grand Prix. On that occasion, the teams racked up around 11,000 kilometres between them in two days, giving them a good initial taste of Pirelli's new tyres.

The Italian company will bring a wider range of the new Formula One compounds to Valencia this week, having defined the specification at the final private test sessions in the United Arab Emirates throughout mid-January

As well as the dry tyres, Pirelli will also put the intermediate and wet tyres at the disposal of the teams in case of rain: a frequent occurrence on the Spanish coast at this time of year.

During the three-day Valencia test, each of the 12 teams will receive a maximum allocation of 30 sets of tyres. The teams can choose how many sets of each compound they wish to test, depending on their individual development strategies.

The same arrangements will be in place for the following two tests, which will also take place in Spain: Jerez (10-13 February) and Barcelona (18-20 February).

All the teams will be able to rely on the support of the entire Pirelli F1 squad in Valencia, which is composed of 50 people. In particular, each team will have its own allocated Pirelli engineer, tasked with passing on technical information and working together with the team to help set up the car.

So far, Pirelli has covered more than 18,000 kilometres in 10 private tests including two days at Valencia last October when the intermediate and wet tyres were tried out for the first time

"We arrive in Valencia with all our compounds defined and ready to offer the teams different tyre solutions," said Pirelli's Motorsport Director Paul Hembery, "having enjoyed an intense and fruitful collaboration so far. This test will provide us with some useful feedback and a valuable taste of the season to come. It goes without saying that we are eagerly awaiting the first Grand Prix. Valencia will be a very significant test, as it will allow us to experience a situation that is very similar to real race conditions, although the ambient conditions aren't representative of the rest of the year, and also give us a good idea of how to work together in future. The objective of this test is to give all the teams the opportunity to become better acquainted with the tyres that we will supply to them this season, before they end their development programmes prior to the first Grand Prix of the year in Bahrain."