Difference between 特色, 特點, 特性, 特質, and 特徵
The words can be differentiated as follows:


特色 - style (abstract)
特点[點] - unique point (general)
特征[徵] - feature (of a person or a product)
特质[質] - quality (of a product or a person)
特性 - property (abstract)


These are usually non-interchangeable if you are specific about what you are saying or writing. An example statement combining all the above would be:


  这台相机有许多特征：它具有防水功能的特性，优良特质的防刮镜头，最主要的特点是它无需对焦就能让你拍出据有专业特色的照片。
  
  This camera has numerous features: it has a
  water-resistant property, excellent quality scratch
  resistant lens. The most important (unique) point is that it doesn't
  require focusing and can let you shoot photos with a professional style.


The most appropriate character for X that I can think of is:


文化特色 - (cultural style)
個人特徵 - (personal feature)
產品特質 - (product quality)
語言特性 - (language property)
時代的特點/徵 - (unique point or feature about an era, epoch or period of time)