Well, I must say, I am very dissatisfied with the VapCap I received today. The cap is so loose it just falls right off. I did read in this thread about squeezing the cap slightly to tighten the fit but this cap is so far out of spec that if I squeezed it enough to hold it on, it would be so egg-shaped that it would be ruined. If Dynavap offers to send a free cap that is in better spec, I'll try that but otherwise, I'll be returning this for a refund. Sure took the wind out of my DynaVap sail.