Compositions that contain a co-particle, a bleach catalyst, and optionally, a detergent adjunct material are disclosed. The lens barrel has a lens and an image pickup device embedded therein. The header generator provides a first header comprising a first sequence number field that determines the order in which a receiving entity present the first data unit to higher protocol layer. The bottom of each angled bracket is flush with the top the paving stones. The track extending portion is oriented at an angle with respect to an axis oriented transverse to a ground surface such that the track extending portion has a continuous slope with respect to the ground surface.