A no turn mattress basically means that it is one sided and does not require flipping over. There are pros and cons to this depending on your circumstance. First, the pros are that there is far less maintenance and hassle as you do not have to flip every few months, this can be more of a pain than you think given the weight of the product and also whether or not it features turning handles. There are a few cons however, namely when it comes to wear and tear. A non-flip mattress has the comfort layer on the top and so your maximum surface area is halved over a double sided mattress which can increase wear and reduce lifespan. Nowadays quality standards prevent this from being too much of an issue and expected lifespan of a one-sided mattress is still a fairly long time.