how to distinguish between old 15w and latest 25w new versions of iPhone Mag Safe chargers

You can identify it by the model number. MagSafe chargers compatible with the 25 watt delivery are models A2580 or A3250.

The one you show is the older model.

click here ➜ How to get up to 25W wireless charging with MagSafe Charger with iPhone - Apple Support

-g wrote:

I presume the difference between Apple Mag Safe models A2580 vs A3250 is the 1 meter or 2 meter cable options

Yes. Correct.

I don't see a like or up not option on your post -- I am Ising ancient Mojave/iMac 2107 hardware -- will hit it when I get to a newer device

I presume you already did it, but you can press the up arrow under the post to like it, and up-vote it. Thanks.

Sizes for comparison. The 25w is both thicker and larger in diameter than the 15w.

Peace*

The newer model doesn’t have that thick mold piece behind the USBC plug or under the round MagSafe charger. If you look at the picture the thick mold piece is on both ends of the cable, therefore it’s the 1st generation MagSafe charger. You can also see that thick mold piece on the front of the box where the wire goes into the MagSafe charger which confirms that it’s the 1st generation charger. The new braided cable doesn’t have this mold piece on neither end. I hope this is helpful to others.

The first clue, for me, would have been the "2020 Apple Inc." in the bottom left corner of the box. I dont order any electronics from Amazon, anymore. I ordered an Apple Keyboard and mouse, because I didnt want to drive 40 miles to the apple store, and I could get it in an hour. When I received it, I put the serial number into apples database, and the serial number didnt exist for the keyboard or the mouse. Frustrated, I returned them, and went to the apple store the next day, and just for my own piece of mind, I checked the serial numbers and they were legit.

Yes also the Amazon listing actually has the model number. So this is buyer error, not seller error. Always check model numbers especially when you know there are two versions. Best it also still sells the 15W ones and they are priced cheaper and there is nothing wrong with selling a product that still works. On best buy you’ll see that a distinguishing feature of the 25W version is they actually put 25W in the title as does the Apple Store. One would expect once Amazon has inventory they’d be doing the same.