Res-O-Tone Hazy" refers to a type of drumhead  by Dunnett Classic Drums, ( made by Remo ) These heads are known for their unique sound and feel, which is achieved through a proprietary tympanic film and a lack of coating. The "Hazy" designation typically indicates a single-ply, uncoated head, which is designed to produce a bright, open tone with a good amount of sustain. 

• Proprietary Tympanic Film:

  The core of the Res-O-Tone sound is the special film used in their construction, offering a distinct tonal quality.

• Uncoated:

  The lack of coating on the head contributes to a bright, open, and un-muted tone.

• Good Tensioning and Stick Response:

  Res-O-Tone heads are known for their ability to maintain tuning and provide excellent stick response across a wide range.

• Clean, Open Tone:

  The combination of the tympanic film and lack of coating results in a clear, resonant sound that is both familiar and unique.

• Versatile:

  While often used on the resonant side of drums to enhance tone and range, they can also be used on the batter side, especially for certain playing styles. 

In essence, Res-O-Tone Hazy drumheads offer a distinctive sound and playing experience that is favored by many drummers for their brightness, openness, and excellent response.