2. Circular Glass Cutter
Device for museum heists and object of desire for mischievous, adventure seeking boys.
"When a character has to get through glass, they cut out a perfect, round hole while leaving the rest of the panel untouched. It's a stealthier, quiet alternative to smashing the glass.
It's a suction cup with an attached lever, with a cutting element on the end of the lever. The suction cup is applied to the glass, then the lever is moved around in a circular motion, cutting a circular area out of the glass. A Phantom Thief or spy might use this method during a heist." ( tvtropes.org )