It must be a timing CHAIN ( the Gates website does not list a timing belt for the 3.5 )
Timing chain
2006-2010 v6 has a chain
The '99 Toyota Rav4 2-door has a timing belt, not a timing chain.
Timing Chain
Timing belt
It has a timing BELT
Chain
timing chain
timing chain
chain.
The 2006 Toyota RAV4 4cyl has a timing chain.
The 2.0 liter 4 cylinder in a 2003 Toyota RAV4 has a timing CHAIN