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MC4 weatherproof plugs and sockets are an easy and convenient way to make electrical connections to solar panels (PV panels). MC4 connectors are not suitable for daily disconnection. MC4 is a development of the MC3 standard.

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MC4 plug set (+/-) for 4-6 mm cable, price 10 eur
suitable for cables with an outer diameter of 5,5 - 9 mm
 
MC4 branch socket set (++ - and - + sides) for connecting panels in parallel, price 25 eur
 
SolarWorld Suncable 1x4 mm2 UV resistant solar panel cable, price 3 eur / m
Outer diameter 5,6 mm, tin-plated fibers, color: black
 

Prices include km 20%

PV panel connectors and UV resistant connection cables