Ultrasound therapeutic treatment handpiece

The design is the visual features of the ULTRASOUND THERAPEUTIC TREATMENT HANDPIECE shown in solid lines in the drawings, whether those features are features of one of shape, configuration, ornament or pattern or are a combination of any of these features. The drawings show two variants of the design. The stippled lines do not form part of the design. A shaft portion of the ultrasound therapeutic treatment handpiece varies in length within the break lines, as shown in the drawings. Drawings of the design are included, in which: FIG. 1 is a top right perspective view of an ultrasound therapeutic treatment handpiece showing a first variant of the Design; FIG. 2 is a bottom left perspective view of Figure 1; FIG. 3 is a top view of Figure 1, and is also a top view of Figure 9; FIG. 4 is a bottom view of Figure 1, and is also a bottom view of Figure 9; FIG. 5 is a left view of Figure 1, and is also a left view of Figure 9; FIG. 6 is a right view of Figure 1, and is also a right view of Figure 9; FIG. 7 is a front view of Figure 1; FIG. 8 is a rear view of Figure 1, and is also a rear view of Figure 9; and FIG. 9 is a top right perspective view of an ultrasound therapeutic treatment handpiece showing a second variant of the Design.