Insert the tips of the round nose pliers in the retainer ring's holes and push both together so the oval is almost closed. This tightens the ring.

Once the retainer ring is "tight", push it in top of the axel to insert it in its original position. Take note that the ring is oval shaped and this matches the shape of the axel.

After making sure the blade socket is securely fastened to the axel by the ring, insert the silicone cover.