A fluid drop dispensing device (10), particularly suited for ink jet printer heads, in which a circular electroactuator (22) is supported in concentric relationship with inner (14) and outer (12) ring members defining an annular chamber (16) which is reduced in volume upon excitation of the electroactuator (22). The chamber is defined as a peripheral groove in one or the other of the inner and outer rings and is rendered fluid tight exclusively by peripheral ring surface contact maintained by hoop stress in the two rings as a result of press fitting the inner ring into the outer ring. Both rings may be of plastic material selected for appropriate characteristics or in the alternative, the outer ring may be of plastic while the inner ring is metallic and fabricated of stainless steel or nickel, for example.