Red Bull team principal Christian Horner wants further clarification over Mercedes' DRS-activated F-duct so that other teams can make a fully-informed judgement over whether they should invest in the technology.

13985 - Horner asks for further F-duct clarification

The Mercedes features a duct in the rear wing end plate that is exposed to airflow when the driver activates the moveable rear wing. It is believed the duct channels air to certain parts of the car in order to reduce drag and boost top speed, which is especially useful in qualifying when DRS use is unlimited.

Red Bull and Lotus raised questions over the design at the opening round in Australia, believing that it is driver-activated and therefore could be illegal. The FIA has declared the system legal, but Horner said the main concern now is that other teams will invest in their own designs only for the system to be declared illegal at a later date, as the original F-duct was in 2010.

"[FIA technical delegate] Charlie [Whiting] gave an opinion it, I think in Australia," Horner told Sky Sports. "I'm not sure if he's actually commented on anything here [in Malaysia] and Red Bull isn't the only team that's asked for clarity on this.

"If it's accepted and acknowledged by the FIA then no problem, but we want clarity going forward so we know whether it's a technology we should be looking at, researching and perhaps investing in or is it something that will be outlawed moving forward. I think that's the most important thing for us, just to have that clarity moving forward."

He said Red Bull and other teams are hoping their questions will be answered ahead of Sunday's race.

"I think a couple of the teams are a little bit more animated than Red Bull," he said. "But there's been a bit of dialogue over the last 24 hours and hopefully it can be brought to a conclusion pretty shortly."

Looking ahead to qualifying, Horner admitted that Red Bull would struggle to match McLaren and Mercedes.

"McLaren's single-lap pace looks tremendously strong at the moment and our race pace is looking quite encouraging," he said. "You always want more, you always want to fight more and we've got things in the pipeline that will hopefully help in race pace and single-lap pace. Certainly the one to watch over a single lap is very much Mercedes, they in particular look very strong."