he Yonex Muscle Power 21 badminton racquet is a even balance racket with a medium flex shaft. Excellent badminton racket for all around game.

Muscle Power is Yonex's futuristic design of rounding corners to help realize the frame's full power potential. Instead of seating the string on the sharp points of a traditional grommet hole system, Muscle Power seats the string on Round Archways that cause no string stress-load and no fatigue through contact friction. The construction creates total unity of the frame and string because they are in much closer and tighter contact. The face stability that results from rounding the corners lets you smash with a new magnitude of aggression.

"Durability" helps hold tension
Compared with the Muscle Power construction, a conventional badminton racquet's less durable construction demonstrates a sharp and progressive curve of diminished string tension over time.

String tension remains at its peak
Seven days after stringing, the stringbed of the Yonex Muscle Power Frame badminton racquets continues to provide constant high resiliency for powerful hits.

Energy transfer is maximized
No energy is lost. No energy is wasted. Compared with the conventional badminton racquet, the Yonex Muscle Power constructioin keeps the badminton racquet frame and string in closer and tighter contact so that they function as a single unit to transfer the full magnitude of smash energy at impact directly to the shuttlecock. At the split-second of impact, the entire frame "receives" the full magnitude of the hit, instantly snapping the shuttlecock away with explosive power.

New gateway to speed
Yonex Muscle Power badminton racquet's explosive combination of advanced construction and performance features -- Round Archways - total unity of the frame and string - outstanding face stability and durability - and consistent playability across the entire stringbed -- pack 5% more speed into smash shots. Enough to win the edge over any competition.