Le sexe à la barre (1975)

Longtime friends Marc and Hubert are successful CEOs in their 50s married to beautiful women. When they begin to doubt their power of seduction, they send their wives on a trip together and start seducing other women, which leads to some sexual escapades. Rejuvenated, they join their wives, but their holiday is quickly disrupted by the intrusion of young sexy campers who bring a wind of erotic freedom and teach the older couples to reevaluate their lives.