Bovril handy-book & diary of the War
The pattern
This still is filed under Utility premium.
Define
The free thing is kept because it works (a calendar, a tool, a template) and the brand rides along.
Mechanism
Usefulness as media. Frequency of use is frequency of exposure. Distinct from a keepable card: here the object has a job.
Verdict
We can give something people will actually use next week.
Why it works
Tying the brand to the most important current event (WWI) by providing a useful timeline and insignia guide ensures high retention of the marketing material.
Steal this when
You want to create a high-utility premium by providing reference information about a massive cultural event your audience cares deeply about.