Lightest most compact closed-cell mattress. Still a favorite of the ultralight elite, the Z Lite mattresses are our lightest, most compact closed-cell mattresses. Both the Z Lite SOL and the original Z Lite feature a compact accordion-style shape and heat-trapping dimples. The proprietary foams are softer on top for extra comfort and denser on the bottom for extra durability. Wherever you're headed, a Z Lite mattress is the right choice for ultralight warmth, durability and comfort. Compact Design: Folding design is compact and easy to pack. Extra Durable: Virtually indestructible closed-cell foam provides lasting, economical comfort.