5 X 15cm heat pad

Tell me, folks… could multiple pads (3) be spliced together and run off a 9V transistor battery?

I’m looking to keep my wife’s Oboe (woodwind Instrument) warm during the cold weather

Please advise.

You really should use 5V or 4.8V (4xAA alkaline batteries). A 9V battery won’t last long, and the voltage is too high.
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