Or techno - cigar addled butts, if so inclined...
Really, a single device like GPS, MP3, Cell, etc. draw typically less than 1A each for trickle charging their internal battery worst case, so a 5A or 7.5A fused cigar/acc one like HD w/ cover is more than sufficient. If moisture is concern, after wiring it in, use heat shrink tubing and RTV to cover metal/insulated connections and back shell/panel and dielectric grease inside will prevent intrusion/corrosion. :s
Really, a single device like GPS, MP3, Cell, etc. draw typically less than 1A each for trickle charging their internal battery worst case, so a 5A or 7.5A fused cigar/acc one like HD w/ cover is more than sufficient. If moisture is concern, after wiring it in, use heat shrink tubing and RTV to cover metal/insulated connections and back shell/panel and dielectric grease inside will prevent intrusion/corrosion. :s