You'll only have to be stranded one time at an airport with limited services and find one or several of your landing gear tires to be low on air pressure, to appreciate this

Milwaukee Model 2475-20 portable air pump.

Since I've already got a ton of Milwaukee M12 and M18 battery powered tools, this was an easy call for me to buy and carry in the plane with my AOG gear. It is lightweight and the M12 Li-Ion batteries don't easily discharge much over time.

This little pump is so convenient, the significant other loves to have it in her car for emergency air needs and I keep one in my vehicle as well. 

This unit easily gets my 60psi main gear tires topped up without breaking a sweat and still has plenty of battery capacity remaining. I roll with a 7Ah generic battery to keep costs low, while the 7Ah insures that I have lots of capacity between charges and this pair is only $35 at Amazon.

Or get this Battery & Charger Combo kit from Amazon for about $31 to run your pump

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