Advantages

• intended for repeated use
• can be inserted without prior shaping
• available for different ear canal dimensions, and with flanges of
  different softness levels
• economical
  
  

Disadvantages

• can cause an unpleasant sensation of pressure in the ear canal
  
  

Product life

One week to several months

• Expanding foam ear plugs
• Pre shaped ear plugs
• Wadding
• Custom ear molds
• Ear plugs with frames