This is a continuation of a prior patent. But strange that it is issued just a few months after the prior one issued in Dec 2013. There may have been claims disallowed with the prior patent that are now allowed.
The term “continuation application” refers to an application that is based on an original patent application (often referred to as a “parent” application), and has the same priority date and specification as the parent. When an application is a continuation of a parent application, it "claims priority" to the parent application. Continuation applications are often filed so that an applicant may pursue claims to inventions that were disclosed but not allowed in the parent application.