The two most common types of clarinets are wood and plastic. Beginners typically use plastic clarinets because they are less expensive and more durable. Most professionals use wood clarinets for their rich warm sound. Wood clarinets can also crack in cold, hot or moist conditions, so musicians who perform outside tend to use the more stable plastic clarinet. Plastic clarinets are usually made of resin while wood clarinets are usually made of African Grenadilla wood.
Examine the outside of the clarinet. Wood clarinets will have a dull grain appearance while plastic clarinets tend to be smooth and shiny.
Look down the inside of the clarinet. A shiny interior indicates a plastic clarinet and grain texture indicates wood.
Test the weight of the clarinet. Wood clarinets typically weigh more than plastic ones.
Rub your finger along the outside of the clarinet. Wood clarinets feel soft as if you could rub the grain pattern out while plastic clarinets feel hard.
Feel the inside of the clarinet. Wood clarinets have a rough ridged feeling and plastic clarinets are uniform and smooth.