Review on Yealink T4 Series Expansion Module by Tom Ball

This expansion module is a great addition to ANY office's phone system. According to my experience, it is easy to install and allows me to have quick access to frequently used functions. The added convenience of having more programmable keys is a game-changer. The only downside is that it can be a bit pricey but in the end, it's worth the investment for the added functionality. Overall, i highly recommend this product for anyone looking to enhance their telecommunications setup..