Run the file through a service like VirusTotal before extracting.
Based on the naming convention typically used in niche music production and digital sheet music communities, it most likely contains one of the following: pianoextra02.rar
A batch of PDF scores, possibly part of a series (given the "02" suffix). Run the file through a service like VirusTotal
Could you tell me or what you expected it to be ? Knowing the context or the file size would help me provide a much more detailed review of its contents. please be cautious:
Since this file is not from a verified official source, please be cautious: