The father of Henry Surtees has suggested that Lewis Hamilton should re-think his position on 'halo'.
Some of the Mercedes driver's colleagues have also admitted their opposition to the safety device, but Hamilton went a step further by calling it the "worst-looking mod in F1 history".
Hamilton's Instagram post was subsequently deleted, but he also told reporters at the end of the Barcelona test: "I hope we have an option to use it or not because I will not be using it."
F1's champion before Hamilton, Sebastian Vettel, disagrees with the Briton, saying that 'halo' may be "ugly" but "nothing justifies not having these two guys around anymore".
The German was referring to Indycar's Justin Wilson and also Surtees, an 18-year-old who was killed when debris struck him on the head during a F2 race in 2009.
"Sebastian hit the nail very clearly on the head with what he said," The Telegraph quotes 1964 world champion John Surtees as saying.
"Lewis could perhaps think a little more about the halo and think about the responsibility he does have as a world champion. He could actually consider this and, if possible, give the maximum input into making certain that it is as less intrusive as possible.
"I suffered the tragedy of losing Henry which certainly could have been prevented by a development like this."
The new Formula 1 season begins with the Australian Grand Prix in just over a week's time.
