Froli sleep systems promote healthy sleep and at the same time save a lot of space and weight. If desired, the degree of hardness can be increased in various areas, e.g. for lordosis support, by subsequently clipping in clamping crosses. A standard mattress, preferably cold foam or latex, serves as a support. In a handy basic package there is a complete kit for the standard dimensions of lying surfaces in touring vehicles. The Froli extension package adds missing elements in case of deviations from the standard dimensions. The systems can be clipped tightly or wide by selecting the hole spacing. The degree of hardness for the respective body weight can be varied accordingly. Scope of delivery Extension package Froli Travel: 12 spring elements (1), 12 base crosses (2), basic package Article no. 93010. See table for calculation example