Red HTC Thunderbolt 4G LTE Extended Battery Thermoplastic TPU Cover Case (Universally Compatible with HTC, and Seidio) Designed specifically for the HTC Thunderbolt 4G LTE Generic extended battery and cover Access to all phone ports and buttons. Open access to speakers, microphone & camera.. Manufactured from Thermoplastic Polyurethane TPU. Will NOT stretch out or collect lint Compatible with HTC/Verizon 2750mAh Extended Battery Compatible with Seidio 3200mAh Extended Battery