... dimensionsΦ3mm/Φ4mmExternal size: The advantages of my solar junction box:This SC-JB2 Junction box confirms to TUV approvalSimple, safe, fast, reliable, connective ... its outstanding anti-aging, water-proof and UV-resistance propertiesOur junction box is with the lowest contact resistance:0.4mΩ,which enables ... product, designed to suit both financial and specification constraints. solar PV junction box2