not going to spend a lot on a basic item and this fits the requirements
very good value
Cheap enough to be able to carry several in case of punctures and durable enough to not need them
Good value and does exactly what it should
Decent tube for the price of 1.99 , will buy again if needs be.
Fills with air
keeps the air in :P
Great value and good to have in your bag
Its an innertube. It goes in the wheel, and it inflates. Nothing more to add.
"The wheels on the bike go round and round"
It pumps up
It doesn't go down