various piezoelectric ceramic from beijing yongda ultrasonic,

disc piezoelectric ceramic:
http://www.ydaultrasonics.com/products/disc-piezoelectric-ceramic

ring piezoelectric ceramic:
http://www.ydaultrasonics.com/products/ring-piezoelectric-ceramic

tube piezoelectric ceramic:
http://www.ydaultrasonics.com/products/tube-piezoelectric-ceramic

cylinder piezoelectric ceramic:
http://www.ydaultrasonics.com/products/cylinder-piezoelectric-ceramic

square/rectangular piezoelectric ceramic:
http://www.ydaultrasonics.com/products/square-rectangular-piezoelectric-ceramic

ball/hemisphere piezoelectric ceramic:
http://www.ydaultrasonics.com/products/ball-hemisphere-piezoelectric-ceramic