The Peek-A-Boo Gary Band is a toy that was sold in Burger King kids' meals during October 2011. The toy was a pink headband with two lime-green spheres made to look like the eyes of the Gary character.
The toy's description from Burger King's no-longer-running Club BK website:
"Look like Gary with this eyeball headband. It has eyes that wobble and glow in the dark!"