Robert Kubica says it's too early to assess the effectiveness of the new front wings for 2019.
Several teams, including Williams, were running 2019-spec front wing designs at the post-Hungarian grand prix test this week.
'It's wider and you feel it'
The wings are designed to help boost overtaking from next year.
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"It's wider and you can feel that. But it's too early to have a good opinion about it.
It was a test for our aerodynamic engineers so that they can collect data about how the air flow is affected and so on," Polish test driver Kubica said in Budapest.