Outdoor if you have a tire inflator, thats would be great. Nowadays we found powerbank inflator is popular, we tested and we suppose if it is out of power, how we do?
So we come out this simple structure tube inflator, it is more than a tire pressure equalizer, you can share 1 or other 3 tire to flat one, generally 20 PSI can drive, more or less, will not damage tire or rims. so this tire pressure equalizer could drive you to garage at least.
Light, small, easy use. and it is inexpensive. carry it for outdoor driving, hope you will not use it. but tomorrow or accident, God knows which one comes