WORKS WITH VOIP LANDLINE, BUT DOES NOT WORK WITH BUSINESS VOIP. CALLER ID SERVICE IS REQUIRED FROM YOUR NETWORK PROVIDER FOR THIS PRODUCT TO WORK. Quality and Customer Support: CPR offers excellent customer support, ensuring that any issues or queries you have about the product are addressed promptly and effectively. This level of customer service sets it apart from many competitors. CPR is known for its high-quality build and durability, ensuring that it will last longer and perform better than many other call blockers on the market. Don’t let another unwanted call interrupt your day. Easy Installation & Compatibility: The Call Blocker is designed for easy setup, making it user-friendly even for those who are not tech-savvy. Many competing products require complex installation processes. Compatible with all landline phone systems, including VOIP, making it a more versatile choice compared to other call blockers in the market. Whitelist Feature: Unlike many other call blockers, the CPR V10000 offers a whitelist feature. This allows you to prioritize calls from specific numbers, ensuring that you never miss an important call from loved ones or business contacts. Pre-loaded Nuisance Robocall Database: The CPR V10000 comes pre-loaded with a database of known nuisance robocall numbers. This feature, not commonly found in competitors' products, provides immediate relief from unwanted calls plus you have the ability to block a further 2,000 unwanted numbers at your discretion.