The CT14 has all the features of the CT11/CT12 (except speed dial and Firefly™ in the headset). The main difference is the wireless frequency. CT14 uses DECT 6.0 and the CT11/CT12 uses 2.4 GHz. DECT 6.0 is a voice-dedicated 1.9 Ghz frequency that provides high-quality sound and will not cause interference with Wi-fi networks or home appliances. Interference is an issue with many 2.4 Ghz cordless phones. The CT14 has some feature improvements which include: · Longer talk time: 10 hours vs. 5.5 hours · Increased range: 300 ft. vs. 150 ft. · Multi-unit capabilities, such as intercom and 3-way conferencing features.