Klein Tools CL390
#3 in AC/DCFull review
An affordable true-RMS AC/DC clamp that suits DIY solar, automotive and general electrical work.
Amazon $86.27$86.27
The Klein Tools CL390 is the better clamp meter overall, rated 3.7 to 2.9. The Klein Tools CL390 leads on current range, safety rating and jaw opening. The UNI-T UT210E wins on price. The UNI-T UT210E costs $26.88 less ($59.39 vs $86.27).
Prices were last checked November 9, 2026. Product prices and availability are accurate as of that date and are subject to change; the price and availability shown on Amazon or the retailer's site at the time of purchase apply. As an Amazon Associate we earn from qualifying purchases.
UNI-T UT210E
#11 in AC/DCFull review
A pocket AC/DC clamp for automotive, electronics and small-appliance work where low-current resolution matters more than range.
Amazon $59.39$59.39
Which should you buy?
- Choose the Klein Tools CL390 for current range (400 A through the jaw vs 100 A through the jaw), safety rating (CAT III 600 V vs CAT III 300 V / CAT II 600 V) and jaw opening (41 mm jaw vs 17 mm jaw).
- Choose the UNI-T UT210E for price ($59.39 vs $86.27).
Scores side by side
Each factor is scored 0-100 against the same fixed reference points for every AC/DC clamp meter; a clear win is highlighted. How we rank explains each one.
| Factor weight | Klein Tools CL390 | UNI-T UT210E |
|---|---|---|
| Overall rating | 3.7/5 | 2.9/5 |
| Current range 15% | 46 400 A through the jaw | 0 100 A through the jaw |
| DC current 15% | 100 DC current to 400 A through the jaw | 100 DC current to 100 A through the jaw |
| Safety rating 20% | 55 CAT III 600 V | 25 CAT III 300 V / CAT II 600 V |
| Features 15% | 50 true RMS, non-contact voltage, temperature, DC microamps | 45 true RMS, non-contact voltage, low-pass filter |
| Accuracy 10% | 67 2% of reading | 50 current accuracy not published (neutral score used) |
| Jaw opening 5% | 70 41 mm jaw | 0 17 mm jaw |
| Warranty 10% | 50 2-year warranty | 0 warranty not published, scored as none |
| Price 10% | 76 $86.27 | 93 $59.39 |
Specifications
| Klein Tools CL390 | UNI-T UT210E | |
|---|---|---|
| Measurement | ||
| AC current (jaw) | 400 A | 100 A |
| DC current (jaw) | 400 A | 100 A |
| DC microamps (leads) | 200 uA | - |
| Voltage | 600 V | 600 V |
| Current accuracy | 2% of reading | - |
| Jaw opening | 41 mm | 17 mm |
| Safety | ||
| CAT rating | CAT III 600 V | CAT III 300 V / CAT II 600 V |
| Features | ||
| True RMS | Yes | Yes |
| Inrush | No | No |
| LoZ mode | No | No |
| Non-contact voltage | Yes | Yes |
| Low-pass filter | No | Yes |
| Temperature | Yes | No |
| Phone app | No | No |
| Build | ||
| Weight | 291 g | 170 g |
| Warranty | 2 years | - |