Design concept: It is derived from the two letters "WM". The shape of the two letters "WM" is reflected in both the main body and the hollowed-out interlocking part. Therefore, it is named "WM". As some players think it looks like Batman, it also has the name "Batman".
Hollowed-out interlocking part: Place a 2.778 steel ball above and below the weight - reducing hole of the main body. When the interlocking part rotates freely, there will be the sound of wind chimes. The principle is that the hollowed - out interlocking part blocks half of the ball. When it rotates, the interlocking part will toss the ball up and then the ball will fall. Repeating this process, a clear wind chime sound is produced.
