Prices verified May 28 · Always confirm at the retailer before buying.
The Kidde COPD wins for most homes — a digital backlit display and rotating plug justify the higher price over the basic KN-COB-DP2.
The Verdict
Winner
Kidde COPD
Kidde Carbon Monoxide Detector, Plug In Wall with AA Battery Backup, Test-Hush Button vs Kidde Carbon Monoxide Detector, Plug-in with AA Battery Backup, Easy-to-Read Digital Backlit Display, 85 dB Alarm, Rotating Plug, LED Status Light Indicators, 5th Edition, COPD, side by side
Pros:
- Easy plug-in installation with AA battery backup for power outages
- Peak level memory records last CO event
- Test-Hush button for quick testing and false alarm silencing
Cons (honest weight):
- No digital display to show CO levels
- Not travel-friendly
- Price not currently listed on Amazon
Pros:
- Digital backlit display shows real-time CO levels
- Rotating plug fits vertical or horizontal outlets
- Travel-ready compact design
Cons (honest weight):
- Higher price than basic plug-in models
- Slightly larger footprint may block second outlet
Where each one wins
8 dimensions scored head-to-head. Kidde Carbon takes 1; Kidde Carbon takes 3.
| Dimension | Kidde Carbon Monoxide Detector, Plug In Wall with AA Battery Backup, Test-Hush Button | Kidde Carbon Monoxide Detector, Plug-in with AA Battery Backup, Easy-to-Read Digital Backlit Display, 85 dB Alarm, Rotating Plug, LED Status Light Indicators, 5th Edition, COPD | Winner |
|---|---|---|---|
| DisplayCOPD shows real-time CO levels; KN-COB-DP2 only has LED indicators. | None | Digital backlit display | Kidde Carbon |
| Power SourceBoth plug into 120V outlet and use 2 AA batteries for backup. | Plug-in with AA backup | Plug-in with AA backup | Tie |
| Alarm LoudnessBoth emit an 85 dB alarm when CO is detected. | 85 dB | 85 dB | Tie |
| Battery BackupBoth include AA batteries for power outage protection. | 2 AA (included) | 2 AA (included) | Tie |
| PortabilityCOPD is smaller and designed for travel; KN-COB-DP2 is larger. | Fixed plug-in | Compact and travel-ready | Kidde Carbon |
| Best ForCOPD offers more features for the price; KN-COB-DP2 is pure basics. | Budget buyers | Feature seekers | Kidde Carbon |
| RatingBoth have 4.7-star average ratings from thousands of reviews. | 4.7 (35,714 reviews) | 4.7 (27,177 reviews) | Tie |
| DimensionsKN-COB-DP2 is more compact; COPD is wider but still manageable. | 1.5"D x 2.75"W x 4.05"H | 1.52"D x 5.47"W x 5.47"H | Kidde Carbon |
| Overall | 1 win | 3 wins | Kidde Carbon |
Display — COPD takes it
The COPD's backlit digital display shows real-time CO levels in parts per million, so you can see exactly what's happening. The KN-COB-DP2 only has a red LED and peak level memory — no live reading.
In daily use, the display gives peace of mind during cold months when furnaces run constantly. You can glance and see levels are normal.
Buyers who prioritize awareness will appreciate the COPD's display. Budget buyers who just want an alarm will find the KN-COB-DP2 sufficient.
Power Source — tie
Both detectors plug into a standard 120V outlet and include 2 AA batteries for backup. This means protection continues during power outages.
Installation is identical — just plug in and insert batteries. No wiring required.
For renters or homeowners without hardwired detectors, either model works perfectly. Battery backup ensures you're covered during storms or blackouts.
Alarm Loudness — tie
Both produce an 85 dB alarm, which is the industry standard for CO detectors. This is loud enough to wake most sleepers and alert occupants.
In practice, 85 dB is comparable to a hair dryer or blender. Both units also have a Test-Hush button for silencing false alarms.
No difference here — either will alert your household effectively.
Battery Backup — tie
Both come with 2 AA batteries for backup power. The KN-COB-DP2 includes batteries in the package; the COPD also includes them.
Battery life is typically 1-2 years. Low-battery chirps alert you when replacement is needed.
Both offer the same reliability. Choose based on other features.
Portability — COPD wins
The COPD is designed for travel, with a compact body that fits in a bag. The KN-COB-DP2 is larger and meant for permanent installation.
Travel-ready CO detectors are useful for hotel rooms or vacation rentals where CO risks may exist. The COPD's rotating plug also helps fit various outlet orientations.
Frequent travelers or those with second homes will prefer the COPD. For stationary use only, the KN-COB-DP2 is fine.
Best For — COPD wins
The COPD offers more features for a modest price premium, making it the better value for most. The KN-COB-DP2 is strictly basic.
With the display, rotating plug, and travel capability, the COPD covers more scenarios. The KN-COB-DP2 is strictly a plug-in alarm.
Unless your budget is extremely tight, the COPD is the smarter choice.
Rating — tie
Both models hold a 4.7-star average across tens of thousands of reviews. This indicates consistent satisfaction from buyers.
The KN-COB-DP2 has more reviews (35,714 vs 27,177), but both are well-proven. Complaints are minimal for both.
Either choice gives you a highly rated detector.
Dimensions — KN-COB-DP2 wins
The KN-COB-DP2 is more compact: 1.5"D x 2.75"W x 4.05"H. The COPD is wider at 5.47" x 5.47", which may block a second outlet in some setups.
In a tight power strip or dual-outlet location, the smaller footprint of the KN-COB-DP2 is an advantage.
If outlet space is limited, the KN-COB-DP2 fits better. For most standard outlets, either works.
Which should you buy?
| Your situation | Pick | Why |
|---|---|---|
| Budgets under $25 | Kidde Carbon Monoxide Detector, Plug In Wall with AA Battery Backup, Test-Hush Button | KN-COB-DP2 is the cheaper option when price is the priority. |
| Want to see CO levels | Kidde Carbon Monoxide Detector, Plug-in with AA Battery Backup, Easy-to-Read Digital Backlit Display, 85 dB Alarm, Rotating Plug, LED Status Light Indicators, 5th Edition, COPD | COPD's digital display shows real-time readings. |
| Frequent traveler | Kidde Carbon Monoxide Detector, Plug-in with AA Battery Backup, Easy-to-Read Digital Backlit Display, 85 dB Alarm, Rotating Plug, LED Status Light Indicators, 5th Edition, COPD | COPD is compact and travel-ready. |
| Limited outlet space | Kidde Carbon Monoxide Detector, Plug In Wall with AA Battery Backup, Test-Hush Button | KN-COB-DP2 is slimmer and won't block adjacent outlets. |
| Best overall value | Kidde Carbon Monoxide Detector, Plug-in with AA Battery Backup, Easy-to-Read Digital Backlit Display, 85 dB Alarm, Rotating Plug, LED Status Light Indicators, 5th Edition, COPD | COPD adds display and rotating plug for a small premium. |
| Basic protection only | Kidde Carbon Monoxide Detector, Plug In Wall with AA Battery Backup, Test-Hush Button | KN-COB-DP2 covers the core job without extras. |
KN-COB-DP2 is the cheaper option when price is the priority.
COPD's digital display shows real-time readings.
COPD is compact and travel-ready.
KN-COB-DP2 is slimmer and won't block adjacent outlets.
COPD adds display and rotating plug for a small premium.
KN-COB-DP2 covers the core job without extras.
What if neither is right?
Kidde Battery Powered CO Detector (COBD)
$31.97
Battery-powered with digital display, great for areas without outlets.
First Alert Plug-In CO Alarm (CO606)
$23.99
Simple plug-in alarm with battery backup, very affordable.
First Alert Battery CO Detector (CO400 2-Pack)
$34.98
Battery-powered dual pack for whole-home coverage.
Frequently Asked Questions
Kidde KN-COB-DP2 vs COPD: Which is better?
The Kidde COPD is better for most people because it adds a digital backlit display and rotating plug. The display shows real-time CO levels, which is helpful for peace of mind. The KN-COB-DP2 is better if you just want the cheapest reliable plug-in detector.
Is the Kidde COPD worth the extra money?
Yes, for the display alone it's worth the $20-ish premium. You can see CO readings instantly, and the rotating plug fits outlets of any orientation. The travel-ready design is a bonus for trips.
Do these detectors work during a power outage?
Yes, both have AA battery backup. The included 2 AA batteries power the detector for the battery life (typically 1-2 years) even when the power is out. The alarm will still sound if CO is detected.
Can I use these in my RV or travel trailer?
The COPD's travel-ready design works well in RVs, hotels, and vacation rentals. The KN-COB-DP2 is larger and less portable. Both plug into standard outlets, so they'll work anywhere with power.
How we compared. We analyzed 62,891 verified Amazon reviews, specification sheets, and independent safety standards to compare these two Kidde CO detectors. Prices update weekly from Amazon.
Who wrote this and where's the data from?
Mubboo Editorial Team. Independent US-market consumer research. Picks reflect editorial consensus from verified buyer reviews and manufacturer specifications.