WATERPIK COMPATIBLE MODELS: Compatible with all Waterpik Sonic-Fusion and Sonic-Fusion Professional Flossing Toothbrush models COMPACT REPLACEMENT BRUSH HEADS: Replace Sonic-Fusion flossing brush heads every 3 months ADVANCED DESIGN: Flossing technology is built into the patented brush head; soft, high-low bristles pattern gently brushes while the water Flosser removes plaque and debris from between teeth and below the gum line 2 COUNT: Included within each plastic clamshell package are 2 compact-size replacement toothbrush heads: 1 white with white color ring, 1 white with chrome color ring NO BRUSH HEAD COVERS: Does not include brush head covers