Commercial / Retail / Offices If you are looking for a new or an upgrade for your security camera system. Check out the 720p/1080p HD-TVI line of products. The DVRs are backwards compatible so you can use your old cameras and change cameras out as needed. Best thing is you can use the coax cable that is already in use. Cable running is a costly and labor intensive part of an installation. If you have cable already ran....just upgrade the cameras and DVR. We recommend the 1080p resolution(HD -TVI System Link).