Kevin Magnussen was not impressed with Halo having run it for the first time in Mexico on Friday as he felt it limited visibility.
Renault attached the cockpit protection device to Magnussen’s RS16 at the start of Friday’s opening practice in Mexico City.
The Dane covered several laps with Halo but made it clear that he is not happy with the design.
“[I’m] not a big fan, it feels weird,” he told Autosport.
“It’s like having a cap that’s pulled down far, and you can see where you’re walking, but you can’t see anything else. I don’t like it.
“The visibility is not as good as I’d hoped, so I think on tracks where there is elevation it’s going to be a problem.”
Magnussen, who has yet to learn whether he will remain in Formula 1 next season, believes there are other safety features that Formula 1 can improve before going to cockpit protection, whether that be Halo or something else.
He added: “There are perhaps other things that need to be looked at before something like a Halo, closed cockpit or canopy screen, or whatever.
“Tracks; gravel in many places; what we’ve done with the Virtual Safety Car when there are trucks on the track is very good.
“And anyway, that accident with Jules [Bianchi at Suzuka in 2014, that led to his death] wouldn’t have been any different if he’d had a halo.
“The halo would work in a situation where a wheel hits the head, or maybe a nose cone, which is what happened with Justin Wilson [in IndyCar].
“But in Formula 1 there are other things that need changing.
“I would have preferred to have gravel in Spa, instead of Tarmac run-off.”