The Williams Formula 1 team launched its 2013 car ahead of the second pre-season testing at the Circuit de Catalunya here Tuesday.
The FW35 is a culmination of more than 12 months' research and development by the team's technical departments in Grove and features improvements in several key areas over last year's race-winning FW34.
"Given the rule stability over the winter, I'm pleased with the gains that we've been able to make with this car. It's a better, more refined car than the FW34," said Williams technical director Mike Coughlan.
Despite being an evolution of the 2012 car, more than 80 per cent of the FW35 is new.
It has a new gearbox, new rear suspension, new radiators, a new floor, new exhausts, new bodywork, a new nose and a significant amount of weight has been saved as well, the statement said.
With many new parts on the car, the team has carried out a lot of reliability work over the winter. The gearbox alone has already completed 3200 kms on the dyno, a lot of which was conducted in the form of five straight Grand Prix weekends.
From here, the car will continue to be developed throughout the year, beginning with an aerodynamic upgrade in time for the first race (March 17).
"The Coanda effect is going to be a big thing for us. There's been no rule clarification concerning this area of the car, so we'll work closely with Renault (engine supplier) to maximise the available gains. Use of the DRS is more restricted this year, so we'll take some resource away from that and focus on other areas."
Pastor Maldonado and Valtteri Bottas are the Williams' drivers for 2013.