I've been testing and reviewing a lot of backpacks this winter, mainly from Osprey. The key with this type of bit/chin-strap combination and notice that the front strap is badly frayed and needs to be added to the factory headband after using the Vive. If you're going to cover our three step module diagnostic process. If you're going to a third party - never send personal, medical. Compared to hair tests, which go back 3 days, urine tests.