Historically, we've used latex tubes when going ultra light, but they have their disadvantages. They need to be re-inflated before ever ride, and they are susceptible to damage from heat, oil, and light. They're not all bad however, as they offer a nice ride quality, increased flat resistance, and obviously ultra light weight (typically around 50g).
When we discovered the Vittoria EVO, a butyl tube at a mere 55g, we were pleased. Vittoria told us that when combined with their Open Corsa, the ride quality was very similar to what is found in their Corsa tubular tires, which use a latex tube. If you haven't ridden a Vittoria tubular tire, you are missing out on one of the fastest, most comfortable tire offerings available today. So, the mere comparison to one of our favorite tires warranted a bit of testing. We are pleased to say that we found the marriage of the EVO tube with the Open Corsa Clincher to be a match made in heaven.
The valve length is 42mm, which is fine for most low profile rims, however to keep the weight down, these tubes do not have a removable valve core. We recommend keeping a valve extension around like the ones offered by KCNC.