SKE Compact Size 425VA/240W UPS Battery Backup & Surge Protector for Computer UPS Uninterruptible Power Supply UPS Phoenix VL425

To keep wall phone with power it works good
I have the AT&T Advance phone which is the landline replacement. Basically, it is a cell phone tower with battery. You plug landline phones into this Advance phone tower. I use the SKE UPS to power up the house phone so that if power goes out that I’ll have power to the house phone. It’ll power up the house phone for who know’s how long. It’s compact enough to be a good alternative to a power strip with circuit protection.

Instructions and function very skimpy
Instructions are skimpy. As far as I can tell, the black outlets are not on battery backup. I charged it all night, plugged into one of the black outlets and then cut power to see if it worked. It did not. As fare as I can tell, only one of the white outlets is on battery backup. Not happy.

Excellent Battery Backup
I use this to back up modem, router and switch due to frequent short power outages. Works great and keeps the network up until whole house generator kicks in.No more devices waiting to reconnent on power failure

Inexpensive, effective backup for low power consumption devices
I ordered this to provide backup power for my optical network terminal (ONT) and router. Both devices have low power demands, and I have limited space where they are installed, so I needed a smaller backup device that wouldn’t break the bank. In our area, the power is quite reliable, and I almost never experience long power outages. However, especially in the summer, it’s not uncommon for the power to “blink.” These brief interruptions are frequent enough to take the ONT and router down, which is frustrating because I use an iPad to access the internet, and it isn’t affected by the power “blink.” By providing this backup power, I can avoid those interruptions altogether.I received the backup a few days ago, and upon reviewing the box and manual, I noticed an interesting phrase. The instructions say that it produces a “simulated sine wave.” The common description you see in better quality UPS devices is “Pure Sine Wave.” I wondered if this was just a translation issue or if it was a deliberate effort to mislead buyers into thinking it is a pure sine wave converter when it is not. It just so happens that I have an oscilloscope at my shop, so I stopped by there and checked. It turns out that this UPS produces a square waveform, not a pure sine wave. Generally, conventional wisdom is that sensitive electronic devices should be powered by a pure sine wave. I was concerned whether this would even work for my intended use. I decided to give it a try since I already had it in hand.I charged up the UPS and then connected my ONT and router. I started a YouTube video on my tablet and unplugged the UPS. The UPS sounded an alarm to indicate the power was off and it was running on battery. The video continued to play uninterrupted. I let the video run to completion and even started a second one just to make sure it had not buffered the whole video to the device. I also browsed the web a bit and ran a speed test. My internet connection was not affected.After testing it, I’m convinced that it will work for me. I’ll admit I was concerned at first, but then I considered the AC to DC transformers that power those devices. In both cases, they are inexpensive, switch-mode power supplies. In practice, this UPS worked well for my use. Other features that I like on this device include USB-A and USB-C outlets for powering or charging other devices, a generous five backup-protected plugs, and Ethernet jacks to protect against a surge. Minus one star on my rating for the somewhat deceptive “simulated sine wave” marketing.