Black Twin Size Trundle Bed.
Also you will need to consider the size of your platform Twin bed. You may be lucky to get some good prices because there is intense competition between online furniture stores. Twin size trundle bed for children as they turned out to be the perfect transition from the crib to sleep more comfortably.

Awesome Twin Size Trundle Bed

Cute Twin Size Trundle Bed

Inspiration Twin Size Trundle Bed

Leather Twin Size Trundle Bed

Twin Size Trundle Bed Decorations

Twin Size Trundle Bed Frame

Twin Size Trundle Bed With Storage