Hold the Power/End Key to turn off the phone.
Remove the back cover of your phone.
Carefully insert the battery with the contacts located against the metal springs. 
Push down the battery until it clicks into place.
Replace the cover on the back of the phone.
Hold the Power/End Key to turn off the phone.
Remove the back cover of your phone.
Lift the end of the battery near the bottom of the phone to remove it.
Z331 specifications
The AT&T Z331 is a feature phone designed for users who prioritize basic functionality over complex smart technologies. It encapsulates simplicity, reliability, and usability, making it an excellent choice for individuals who seek a straightforward communication device without the distractions of advanced apps.One of the main features of the AT&T Z331 is its compact and lightweight design. Weighing just a few ounces, it fits comfortably in the palm of your hand and can easily be slipped into a pocket or bag. The device sports a 2.4-inch display, which is bright enough for easy reading and navigational tasks. The display, while modest, offers clear visibility for calls and messages.
The Z331 is equipped with a sturdy keypad that features large, tactile buttons, allowing for effortless dialing and texting. This is especially beneficial for users who may have difficulty using touchscreens, such as seniors or those with limited dexterity. The interface is user-friendly, ensuring that even those who are not tech-savvy can navigate it with ease.
In terms of connectivity, the AT&T Z331 supports 4G LTE, providing users with a fast and reliable network for calls and text messaging. The phone is primarily geared toward voice calls and SMS messages, with basic multimedia capabilities such as camera functionality. It features a 2 MP rear camera that can capture images and videos, suitable for informal photography.
The internal storage of the Z331 is modest but can be expanded with a microSD card, offering users the ability to store more photos and other essential files. The device is powered by a long-lasting battery, ensuring that users can stay connected throughout the day without frequent recharges. The battery life is one of its strong suits, with extended standby time that caters to users' needs.
Additionally, the AT&T Z331 comes pre-installed with essential applications such as a calendar, alarm, and FM radio, enhancing its usability as an everyday device. One notable aspect is its durability, built to withstand daily wear and tear, making it a reliable companion for various lifestyles.
In conclusion, the AT&T Z331 is tailored for those who appreciate straightforward communication tools. With its solid build, user-friendly interface, and essential features, it addresses the needs of individuals looking for a dependable phone while avoiding the complexities often found in smartphones. Its strong emphasis on basic functions makes it a perfect choice for an array of users, from the elderly to those who wish to disconnect from the digital noise of modern devices.