When you're choosing between charge controllers solar BOS components for a small solar array, the combiner box is the unsung hero. It takes four panel strings, feeds them through a protective circuit breaker, and sends one combined output to your charge controller or inverter. Two nearly identical 4-string boxes sit at the same price point, separated by just 63 cents. This head-to-head breaks down the 4String Solar PV Combiner Box and the 4 String Solar Combiner Box so you can see whether the minimal price difference actually matters.
Quick Verdict
Both boxes share the same core specifications: a 63A, 550V circuit breaker, four inputs, one output, wall-mount housing, IP65 weather protection, and an operating range from -30 to 70°C. The 4String Solar PV Combiner Box costs $61.91 and the 4 String Solar Combiner Box costs $62.54. If you simply want the same functionality for the lowest price, the 4String Solar PV Combiner Box is the pick. If you want a named brand and a listing that explicitly says it's for solar panel kits, the 4 String Solar Combiner Box justifies its slightly higher price.
Comparison at a Glance
| Attribute | 4String Solar PV Combiner Box | 4 String Solar Combiner Box |
|---|---|---|
| Price | $61.91 | $62.54 |
| Circuit Breaker | 63A, 550V | 63A, 550V |
| Input Strings | 4 | 4 |
| Output Strings | 1 | 1 |
| Protection Grade | IP65 | IP65 |
| Mounting | Wall Mount | Wall Mount |
| Operating Temp | -30~70°C | -30~70°C |
| Material | ABS, PC | ABS, PC |
Where Each Box Wins
The 4String Solar PV Combiner Box wins on price, coming in 63 cents lower, and its title calls out "Waterproof" for anyone who wants that reassurance at a glance. The 4 String Solar Combiner Box wins on listing clarity, carrying the NaMaSyo name and directly stating "For Solar Panel Kit" in the title, which makes it easier to spot in a search. Unless those differences matter to you, the two boxes are functionally equivalent for a 4-string PV setup.
4String Solar PV Combiner Box 63A Circuit Breaker Solar Panel System Waterproof
This box is the more economical of the two at $61.91. It includes the circuit breaker, a combination lock, and four mounting plates in the package, so you have the hardware needed for a wall-mounted install. The enclosure is ABS/PC with IP65 protection, four inputs, one output, and a 63A/550V breaker. Choose this one if you want the same core functionality for the lowest price. The main limitation is that the title uses "4String" as a single word and doesn't mention solar panel kits, so if you're searching for that specific phrase, the other listing will stand out more. Otherwise, you get the same surge protection and temperature tolerance as the pricier box.
4 String Solar Combiner Box PV Combiner Circuit Breaker 63A For Solar Panel Kit
This box costs $62.54, which is 63 cents more than the competing listing, but it clearly states "For Solar Panel Kit" in the title and carries the NaMaSyo name. The specs match the other unit: four inputs, one output, 63A/550V standard breaker, IP65 protection, wall-mount housing, two surge protection devices, and the same included combination lock and mounting plates. Pick this one if you prefer a listing that spells out its intended use or if the NaMaSyo name matters to you. The only real downside is the slightly higher price, and the title doesn't call out waterproofing even though the IP65 rating is identical to the cheaper box.
Final Choice by Use Case
For a straightforward buy where price is the tiebreaker, go with the 4String Solar PV Combiner Box. For a solar panel kit build where you want a named brand and a title that tells you exactly what it's for, the 4 String Solar Combiner Box is worth the extra 63 cents. If you're indifferent about those details, either one will handle your 4-string setup equally well.
