This appears on the OS 1:50,000 Map as a Symbol Stone but is almost certainly a standing stone on to which a Pictish Symbol has been incised at a later date. It is just off the Gleneagles turn-off on the A9.
Another stone (called Gleneagles B on Megalithic) lies about 300m to the West. RCAHMS labels them the other way round!
Something is not right. This message is just to keep things from messing up down the road