How strong are these magnets in terms of Gauss or mTesla?

I can specify that they are very strong. They are had to separate if the become attached .

Could I attach these to a magnet on a magnetized curtain rod to make it stronger to hold heavier curtains? This is attached to a metal door.

Probably. They are pretty strong. I use them to hold a metal heat propelled fan to the pipe from a wood fire stove.

Will the magnet damage the mechanics of a phone if used to stick to a magnetic phone holder (for car)?

I was thinking exactly the same thing you're asking me. I rea..lly don't know I .won't take a The truly equipment made damage the phone. Example you take a battery put it near your game or your movie you will see colors changing. Suggest you don't do that. Perfect question thank you. Houdini Santos.

6 Pack Super Strong Neodymium Disc Magnets with Double-Sided Adhesive, Powerful Permanent Rare Earth Magnet Fridge, DIY, Building, Scientific, Craft, and Office Magnets, 1.26 inch D x 1/8 inch H

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