The Kryptonite Comet F500 Front LED Bicycle Headlight features a compact and lightweight body with a multi-fit quick release system. The single bright LED makes this small light a great "to see" light. It easily fits all frame tubes/handlebars sizes 22mm to 32mm and grips the bars whether riding road or trails. The quick release strap attachment system makes it easy to take on or off when needed. This light uses 3 AAA batteries (included) that are replaceable and easy to find on Amazon. The compact F500 is incredibly easy to transport, weighing-in at 3 ounces. The Kryptonite Meteor R300 Rear LED Bicycle Indicator Light features a compact lightweight body with a multi-fit quick release system. The three bright LEDs makes this small light a great "To be seen" indicator while riding. The M300 easily fits all seat post sizes 10mm to 32mm whether riding road or trails. The quick release strap attachment system makes it easy to take on or off when needed. The light uses 1 AAA battery (included) that is replaceable and easy to find on Amazon. This compact light is incredibly easy to transport, weighing-in at only 2 ounces.