This Li-Ion replacement cell phone battery w/ Back Door is 100% compatible with the Motorola I30SX NEXTEL. Our batteries and accessories are made with high quality parts and are guaranteed to meet or exceed the original equipment manufacturers specifications at a reduced price. All batteries are tested for 100% quality control assurance. This Motorola I30SX NEXTEL replacement cell phone battery w/ Back Door includes a 1 year warranty to guarantee that it has no manufacturing defects.