Abstract: To prevent snap-over of a flexible connecting tube conducting solar-heated liquid to a mirror which follows the travel of the sun through the sky and then changes to an inverted "night" position, as shown in FIG. 1 at (a), a flexible corrugated or pleated tube or hose (6) with a braid (9) to form a multi-layered structure (6,9) is surrounded by a stiffening jacket (10) in the form of a spiral metal tube with interlocking adjacent windings. The stiffening jacket has the characteristic to dampen movement of the tube and additionally the tendency to retain the tube in straight or at least single-bend position, so that unstable double bends (FIG. 1, B, C) are avoided. This substantially increases the lifetime of the tube. A lubricant (15) may be introduced between the corrugated tube (6) or the braid (9) and the stiffening jacket (10). Preferably, the braid is a wire mesh or braid (9) surrounding the corrugated tube (6).