However, the two gears can vary in size to achieve a different gear ratio. An example of this is in a hand drill, where the drive gear is larger than the driven gear. A pillar drill with a rack ...

(Carl de Souza/AFP/Getty Images)5. The Agassi Idolizer ** A 5.0-5.5. player, he shaped his game and gear after his childhood idol, Andre Agassi, right down to the oversized Head Radical racquet ...

An emergency whistle coupled with a compass is a must-have safety gear when you're heading into unknown territories or going out on an adventure alone. The former can alert others in case of distress ...