Flex-PhonesXL™ Indestructible Headsets for Teens Our award-winning, nearly indestructible Flex-Phones™ for pre-K and elementary school students are now available in a larger size to accommodate older students! Flex-PhonesXL™ headsets for teenagers come with the same great features, such as a single piece construction made of safe, non-toxic, BPA-free EVA foam. Soft and extremely flexible, Flex-PhonesXL™ come with a headband clip to help adjust and configure the fit for virtually any tween or teen. Flex-PhonesXL™ headsets feature an in-line microphone, volume control and both headsets come with the exclusive Dura-Cord™ – the chew, kink and knot-resistant, PVC-jacketed, braided cord.