The ski pole is made of a material having high resistance and being inherently fragile and it is provided, corresponding to the interior or exterior part with at least one structure which extends substantially along the entire length of the ski pole, the structure being made of material...http://www.google.co.uk/patents/US5766708?utm_source=gb-gplus-sharePatent US5766708 - Ski poles for skiers made of material having high resistance and inherently fragile 
