YeeblineUSB Cable with Switch, 3-Pack USB Male to Female Extension Cord Inline Rocker On/Off Switch for Driving Recorder, LED Desk Lamp, USB Fan, LED Strip

I've been using some USB Heat pads inside cushions to help keep the heating costs down, I bought these switches to allow me some control without unplugging them all the time and they work great. I took 1 star off as there is no indication on the switch as to which way is On / Off

Excellent

These are great for inline switching of devices. However, I find a variable resistance is 5-50 ohms per actuation, which may be important for a specific use case, as they were for me. I used them for something else but seem robust.

"Important Note: This cable is ONLY for power supply（Not support IOS system), NOT for Data transfer use."I overlooked this message when I bought these switches. I was hoping to pair them up with an old microphone I have connected to my laptop so that I didn't have to pull the cable out of it each day to turn it off.Powers the microphone superbly, I just can't use it! Nevermind.

Surprising handy items to save you unplugging the USB power cable all the time. Actually, unplugging a usb cable is easy it's the plugging in with the 50:50 change of getting it the right way round that's a pain.All 3 worked fine, and without issue. Also note there is no path for data through these so don't expect connectivity.

Although this does the job that it was bought for (being able to reboot a raspberry PI installed behind a TV), there is a small problem.It appears that there is quite a voltage drop across the switch. When plugged in directly the PI is fine. But when plugged in via this switch, the PI displays the under-voltage lightning bolt. I haven't measured the drop (someone has "borrowed" my meter) but it is a shame.

I got this so I could make sure there was no power drain from my dash cam.Who wants a dead battery first thing in the morning !!

Works really well with my Galaxy Watch 4 original charger! And it doesn't slow the charger down.