There’s a new product on the market called “longevity insurance.” This is really just a new name for an old concept, the deferred annuity. Unlike most annuities, which are purchased with a lump sum and begin paying out soon afterward, these policies typically don’t begin paying anything until some 10 or 20 years after you buy them.

Sales of these annuities were up 35% last year from a year earlier.

The idea is that, if you outlive your life expectancy, you can receive fairly large annual payments in your later years for a relatively small investment upfront. But there are downsides, too, as there can be with any annuity.

If you’re considering such a product, it’s a good idea to discuss integrating it with your current estate plan.