The FDW 5 Inch Gel Memory Foam Mattress has an inch of comfort foam, and 4 inches of high-density base support foam. ... Sizes: Twin, twin XL, full, queen, king, California king .

A California king mattress measures 72 by 84 inches, making it 4 inches narrower and 4 inches longer than a king. Do two twin mattresses equal a King? No. Twin beds are 5 inches shorter than a king.

After testing a twin-sized, 4-inch Lucid Gel Memory Foam Mattress Topper for two weeks, we’ve given our verdict on its performance in temperature regulation, firmness, comfort, detailed exactly ...

Our pick for the best 4-inch twin XL mattress topper is the Serene Hybrid Mattress Topper. It combines gel-infused memory foam with 1.5 fluffy inches of a down alternative material in its included ...

Both twin and twin XL mattresses have a width of 38 inches, which is just enough space for one adult. However, if you like room to stretch out, consider a full mattress instead.