Pirelli's soft tyres have a gold line around the edge of the sidewall this weekend in Malaysia.
The move follows complaints in Australia that the tyre supplier's choice for visibly differentiating the compounds in 2011 - different coloured logo lettering - was not noticeable enough.
Pirelli said the gold band "should make the compound easier to spot on television" from Sepang.
A permanent revision to the markings this year will be announced ahead of May's Turkish grand prix.
At Sepang on Friday, there was higher tyre degradation than was witnessed in Melbourne two weeks ago.
We need to be careful that we don't end up with tyres that are too conservative
Fernando Alonso said a Sergio Perez-style one stopper will be "impossible" on Sunday, and Pirelli's motor sport boss Paul Hembery said a "normal" dry race will see three stops.
"Here it's all about the tyres," Virgin driver Timo Glock told Speed Week. "They last a lap and then start to break down, so it is just about keeping going as long as possible."
Also on Friday, drivers tested Pirelli's new extra-hard tyre that was tipped to be used in Turkey to cope with the famous Turn 8, but it is believed the tyre proved too hard.
"We need to be careful that we don't end up with tyres that are too conservative," warned Hembery.