Are there any recommendations for short term Endowment Policies?

I have spare cash of $10,000
I want a guarantee that I will get back that $10,000 by the end of the policy. Plus additionals.
Are there such thing as short term endowment plans? I understand that the returns will be low but at least by the end of the policy at least there would still be an increase.
Which endowment should I go for? Any good endowment plans out there for that value I put in?