The Highly Educated V3 Titanium Concentrate Nail is the first fully and infinitely adjustable 29mm titanium nail. The V3 fins are able to move freely up & down the entire length of the shaft. This makes the nail height adjustable allowing the nail to work more efficiently with a wider variety of glass domes. The threaded shaft also allows for the counterweight to be removed to accommodate extra small glass joints, or even be replaced with a smaller mm V3 cap. The attached 29mm pieces are compatible and designed to work with the V3 pieces you currently own. The cap volume has been increased from 344.1mm³ (18mm V3) to 1138.9mm³ (29mm V3).