Quinny Buzz 4 Front Wheel Unit The Quinny Buzz 4 Front Wheel Unit is an accessory that is meant to be used with the Quinny Buzz stroller. It converts the Quinny Buzz 3 Wheel Unit into a Quinny Buzz 4 Wheel Unit. The accessory is easily installed with the press of a few buttons & locks into place in the the front axel of the stroller. The Buzz 4 wheel unit provides the user with swivel wheels that can also be locked into place. The Buzz 4 Wheel Unit weighs 5.6 pounds & is 14.5 by 10 by 5 inches in size. The recommended weight for the 4 Wheel Unit is between 5 pounds & 30 pounds. The benefit of the Quinny Buzz 4 Front Wheel Unit is that it converts the Quinny Buzz stroller, which is originally 3 wheel, into a 4 wheel. The benefit of turning the Quinny Buzz stroller into a 4 wheel unit is that it provides the user with a lot more control & stability over rough terrain. The added stability, provides a much more comfortable ride for the infant. Not only does the 4 wheel system improve handling on rough terrain, it makes for smoother, easier handling on normal terrain as well. In an environment with its inevitable dips & bumps, having the 4 wheel system means that for the parent, there will be less effort needed to control the stroller. For the infant riding the stroller, it means that there will be more comfort, more stability, & less irritation from getting jostled around from unexpected bumps & dips.