Here's what other sites are saying:
The North Face Trekr mountain bike jacket for boys combines wind- and water-resistant protection with breathable comfort so he can hit the singletrack in any kind of weather. Ripstop nylon body fabric is complemented by polyester mesh panels under the arms to promote ventilation. Critically taped seams and binding at the hem and cuffs help seal out moisture. The North Face Trekr mountain bike jacket features a reflective logo and a zippered stow pouch on the back; jacket can be packed into its own pouch for compact storage.