Oxballs cock sheaths like the Muscle, Muscle Ripped, or the Daddy (sheaths are sold separately) each include a small, optional, rounded TPR insert that can help close the gap between the tip of your penis and the end of the sheath's channel-- ensuring a firm feel throughout the shaft, with no gapping.

Depending on your size, you might want more than one of these inserts to help fill any gaps in the shaft. That's where the Adjustfit 3-pack comes in!  In this kit, you get three more of TPR inserts for more exact fit choices.

When inserted into the end of the sheath, these clear rubbery inserts keep the cocksheath firm even when you aren’t as firm.  For users with erectile difficulties, this can really help during penetration.

Each insert shortens the inside shaft about 7/8".

Made from TPR. Please note that TPR is a soft, porous material, and will show wear with use.