Be your own hero.
Given the rapid arrival of 27.5-inch wheels to the marketplace, the likelihood of your LBS or trail-side guardian angel not having the corresponding tube is pretty high at the moment. For this reason, we recommend grabbing fate by the horns and stocking up on the Q-Tubes 27.5in Presta Mountain Tube. After all, it's better to be prepared then to be stranded.
The Q-Tubes 27.5in Presta Mountain Tube is available with a 32mm Presta valve and features a width of 1.375 - 1.75 inches.