An article of clothing for children with a hidden harness attached to the interior of the clothing structure and exterior handholds attached to the hidden harness. The fuel cell stack has at least one cell that includes a cathode to which an oxidant is supplied, an anode to which a fuel is supplied, and a polymer electrolyte membrane sandwiched between the cathode and the anode. The boat line management device capable of delivering a boat line from a position on a boat to a boat docking location. Frame parameters may be tailored to individual users and may be controlled by information pertaining to receivers, such as bit error rate of the receiver.