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KINGBOLEN BM550 is the better pick for DIY use because it tests 6V, 12V and 24V batteries, while the Flutree BT105 suits fault-finding with its waveform monitor. The BM550 covers 100-2000 CCA and 2Ah-220Ah across flooded, AGM, GEL and EFB types, against the BT105’s 100-2000 CCA range and 800 stored test records.
- Choose KINGBOLEN BM550 if you work on a mix of battery voltages, including older 6V units — it handles 6V, 12V and 24V in one tool.
- Choose Flutree BT105 if you chase intermittent electrical faults — its real-time waveform monitor catches problems a static test misses, and it stores 800 records.
I compared these two on voltage coverage, test range and diagnostic features like waveform monitoring and record storage. Everything here comes from the listed specifications, not hands-on testing. That keeps the comparison fair and repeatable.
🏆 Quick Picks — My Top Recommendations
Best Overall: KINGBOLEN BM550
Tests 6V, 12V and 24V with 100-2000 CCA and a 4.5-star rating from 1,435 reviews — Check Price →
Runner-Up: Flutree BT105
Stores 800 test records and adds real-time waveform monitoring for intermittent faults — Check Price →
Here’s how the KINGBOLEN BM550 and Flutree BT105 line up on the specs that actually matter for DIY testing.
Full Specs Comparison
| Specification | KINGBOLEN BM550 6V 12V 24 | Flutree BT105 12V 24V Car |
|---|---|---|
| Brand | KINGBOLEN | Flutree |
| Voltage Range | 6V, 12V, 24V | ✅ 12V, 24V |
| CCA Range | ✅ 100-2000 CCA | 100-2000 CCA |
| Power Source | Battery Powered | Corded Electric |
| Color | Black, Red | Yellow |
| Item Weight | — | ✅ 7.2 ounces |
| Dimensions | — | ✅ 2.55 x 0.94 x 5.19 in |
| Battery Types | — | ✅ Flooded, AGM, GEL, EFB |
| Waveform Monitor | — | ✅ Yes |
| Test Records | — | ✅ 800 |
| USB Print | — | ✅ Yes |
| Cranking Test | — | ✅ Yes |
| Charging Test | — | ✅ Yes |
| Alternator Test | ✅ Yes | — |
| Display Type | ✅ Digital | — |
The biggest split for me is voltage coverage: the BM550 handles 6V batteries too, while the BT105 stops at 12V and 24V but gives you 800 test records and a waveform monitor instead.
Individual Product Breakdown
I looked at voltage range, battery type support, diagnostic extras, and how easy each tester is to use on a driveway. Both are aimed at DIY buyers, but they solve slightly different problems.
KINGBOLEN BM550 6V 12V 24V Car Battery Tester
6V/12V/24V | 100-2000 CCA | 2Ah-220Ah | 1.8-inch HD screen | 8.8 oz
- 【6V 12V 24V Battery Tester】KINGBOLEN BM550 battery tester can test all...
- 【Practical Car Battery Analyzer】BM550 car battery analyzer can quickly...
- 【Simple Operation & Accurate Data】The results of the battery test are...
I like the BM550 because it covers 6V, 12V and 24V batteries, which the Flutree simply doesn’t do. It reads SOH, SOC, voltage and internal resistance across 100-2000 CCA, and it supports flooded, AGM flat plate, AGM spiral, GEL and EFB batteries. The reverse connection protection is a nice safety net if I clip the leads the wrong way. The one catch is that it’s not built for deep cycle batteries, so RV house banks are off the table.
✅ Pros
- Covers 6V, 12V and 24V batteries in one tool
- Handles 100-2000 CCA and 2Ah-220Ah
- Supports flooded, AGM, GEL and EFB types
- 4.5 stars from 1,435 reviews
❌ Cons
- Not suitable for deep cycle batteries
- No waveform monitoring or test records
- Screen can flicker if clips aren’t seated well
Flutree BT105 12V 24V Car Battery Tester with Waveform Monitor
12V/24V | 100-2000 CCA | 800 test records | Waveform monitor | 14 languages | 7.2 oz
The BT105 is the better pick if I want to dig deeper into electrical faults. It runs battery health, cranking and charging tests across 100-2000 CCA, and the real-time waveform monitor catches intermittent problems that a static test would miss. I also like that it stores 800 records (200 each for battery, cranking, charging and waveform) and prints reports over Type-C. It only does 12V and 24V, though, so 6V batteries are out.
✅ Pros
- Real-time waveform monitoring catches intermittent faults
- Stores 800 test records with USB printing
- Complies with 10 standards including CCA, JIS, SAE and DIN
- Heavy-duty pure copper clamps and reverse polarity protection
❌ Cons
- Only supports 12V and 24V, no 6V testing
- Far fewer reviews at 27 compared to the BM550
- Corded power source limits where you can use it
Which One Should You Buy?
Honestly, the right pick depends on your garage and what you actually own. If you work on 6V systems or want the most proven option, that changes everything, and so does wanting deeper fault diagnostics.
KINGBOLEN BM550 is right for you if…
- You own a classic car, motorcycle or golf cart with a 6V battery, since the BM550 covers 6V, 12V and 24V.
- You want the safer bet on reliability, backed by a 4.5-star rating from 1,435 reviews and 200+ bought in the past month.
- You just need quick SOH, SOC, voltage and internal resistance readings on a small 1.8-inch HD screen without extra software.
Flutree BT105 is right for you if…
- You chase intermittent starting faults and need the real-time waveform monitor to catch what a static test misses.
- You service several vehicles and want 800 stored test records plus USB printing for organized reports.
- You work on 12V and 24V systems and want compliance with 10 standards including CCA, JIS, SAE and DIN.
❌ Who Should Skip All of These?
If you need to test deep cycle or lithium house batteries, skip both — the BM550 isn’t rated for deep cycle, and the BT105 only covers lead-acid 12V and 24V. You’d be better served by a dedicated deep cycle or lithium-capable analyzer.
For most DIY buyers with a standard 12V car or truck, I’d grab the KINGBOLEN BM550 for its wider voltage range and huge review base. But if diagnosing tricky electrical faults matters more to you, the Flutree BT105’s waveform monitor and 800 records earn their keep.
Frequently Asked Questions
Which is better for DIY use, the KINGBOLEN BM550 or the Flutree BT105?
For most DIY buyers, I’d pick the KINGBOLEN BM550 because it covers 6V, 12V and 24V and has 1,435 reviews at 4.5 stars. The Flutree BT105 is the better tool only if you specifically want waveform monitoring and stored test records. If you mostly check a standard 12V car battery, the BM550 does the job with less fuss.
Can the Flutree BT105 test 6V batteries like the KINGBOLEN BM550 can?
No, and that’s the clearest difference between them. The BT105 only supports 12V and 24V lead-acid batteries, while the BM550 handles 6V, 12V and 24V. So if you own a classic car, motorcycle or golf cart with a 6V battery, the BM550 is your only option here.
Is the Flutree BT105 worth it over the KINGBOLEN BM550?
It depends on what you’re diagnosing. The BT105 adds a real-time waveform monitor, 800 test records and USB printing, which the BM550 doesn’t have. If you chase intermittent starting faults or service multiple vehicles, those extras earn their keep. For simple battery health checks, the BM550 gives you SOH, SOC, voltage and internal resistance without the extra complexity.
Which tester has better reviews, the KINGBOLEN BM550 or the Flutree BT105?
The BM550 has far more feedback with a 4.5-star rating from 1,435 reviews and 200+ bought in the past month. The BT105 sits at 4.6 stars but from only 27 reviews. I’d trust the BM550’s larger sample size more, though the BT105’s higher score is a good sign for its smaller user base.
Do both testers support the same battery types?
Not quite. The BM550 supports regular flooded, AGM flat plate, AGM spiral, GEL and EFB batteries, but it’s not suitable for deep cycle batteries. The BT105 covers regular flooded, AGM, GEL and EFB lead-acid types and complies with 10 standards including CCA, JIS, SAE and DIN. Neither one is built for deep cycle or lithium house banks.
Which one is easier to use for a beginner?
I’d hand the KINGBOLEN BM550 to a beginner every time. It’s plug and play with reverse connection protection, and results show up on a 1.8-inch HD screen with no software needed. The Flutree BT105 is still manageable, but the waveform monitor and USB printing add steps that a first-timer may not need.
My Final Verdict
After weighing both, the KINGBOLEN BM550 is my overall winner for DIY use. It tests 6V, 12V and 24V batteries across 100-2000 CCA, and its 4.5-star rating from 1,435 reviews gives me more confidence than the Flutree BT105’s 27 reviews. The Flutree BT105 is the better runner-up if you need its waveform monitor and 800 test records for chasing intermittent faults.
If you’re on the fence, ask yourself one question: do you own any 6V batteries? If yes, the BM550 is the only one that works. If you’re strictly on 12V and 24V and love detailed diagnostics, the BT105’s waveform monitor is worth it.
WINNER: KINGBOLEN BM550
- 【6V 12V 24V Battery Tester】KINGBOLEN BM550 battery tester can test all...
- 【Practical Car Battery Analyzer】BM550 car battery analyzer can quickly...
- 【Simple Operation & Accurate Data】The results of the battery test are...
Best for most DIY buyers who want 6V, 12V and 24V coverage with 100-2000 CCA and a proven 4.5-star track record.
RUNNER-UP: Flutree BT105
Best for 12V and 24V work where waveform monitoring and 800 stored test records help you chase tricky electrical faults.
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