Want a tool that can help you merge small PST Files into one, then the Sysinfo PST merge tool will be one of the best choices as it can combine multiple PST files at once. The tool provides you an option to merge Outlook Contacts, Emails, Calendars, Journal, and other mail items into a single file. Other important features are:
Combine multiple Outlook data files with emails, contacts, calendars, tasks, etc.
It offers three advanced options to merge multiple PST files into one PST.
Have an option to remove duplicate items from the chosen PST files.
Available Option to apply password in the resultant Outlook PST file.