Instructions For Fitting Doc's Proplugs:
Fitting Doc's Proplugs (DPP) is worded for the right ear:  Pick a DPP from Fitting Set that matches the size of the inner portion of the ear (Fig. 2).  Grasp the DPP with right finger tip in the cup of the right DPP and pinch it with right thumb at the lower curved part (Fig. 2). The arrow top (fin) of the DPP fits into the Crus Helix (Fig 3. #4). Twist with fingertip back and forth to make sure DPP is in tight between the Tragus (Fig 3. #1) and the Antehelix (Fig 3. #3). Do not jam rectangular knob into the right round canal.

Now, do the "HUM" test. HUM, and if the sound travel toward the right ear, you have the correct size. If the HUM test is negative, try a smaller or larger size. With the correct size DPP, the sound will be louder on the right side.

What to do if you feel you are in between sizes? We recommend that you use the largest size that feels snug to you.

Proper Fit Is Key To Ensuring Maximum Comfort And Performance Of Doc's Proplugs