Pursonic Replacement Toothbrush Heads, Compatible with Sonicare Electric Toothbrush 8 Pack

Confusing to know which brushheads are specifically for one you've already order in many cases. Ordered the PURSONIC USB Rechargeable Electric Toothbrush and thought these brush heads would work but they aren't the same size. Wish there was just 1 standard size that all manufacturers used. Ordering 8 Pack Power Sensitive Replacement Brush Heads for Oral-B, 8 Count, hopefully they will fit the tooth brush that I already ordered becuase these ones don't. Posted in case anyone else is confused when ordering.