Abstract: The present invention relates to a synchronized rack and pinion system for extendable rooms for recreational vehicles. In particular, the invention provides a drive system for use in extending and retracting an extendable room on a vehicle frame. The drive system includes at least one pair of parallel rack and pinion systems operatively connected between the vehicle frame and the extendable room, with each pair of parallel rack and pinion systems synchronized through respective drive shafts. The system is operable between a closed position where the extendable room is retracted with respect to the vehicle frame and an open position where the extendable room is extended with respect to the vehicle frame.

Abstract: The invention relates to an anti-tartar composition comprising:(a) 0.5 to 5% by weight of at least one compound selected from among zirconium silicate and hydrated silica;(b) 0.5 to 5% by weight of at least one compound selected from among chlorhexidine digluconate and zinc digluconate;(c) 0.5 to 5% by weight of at least one compound selected from among potassium thiocyanate, glucose oxidase, lysozyme, and lactoperoxidase; and(d) 1 to 5% by weight of at least one acid compound selected from among vitamin C and citric acid.It also concerns the use thereof in combination with food supplements or chewable supports for animals as well as the food supplements and chewable articles thus obtained.The invention applies, in particular, to the control of the formation of tartar in domestic animals such as dogs.