G
Not strictly true mate, most dive shops sell 300bar tanks and will then fill them to 300barHehe can I also be really pedantic and say that there is no such thing as a 4500psi Dive tank (4500psi=310.263 Bar) and Dive cylinders come in either 300 Bar (4351.14psi) or 232 bar (3364.8816psi). The 300 bar cylinders are also not very common and most dive shops only stock 232 bar as 95% dive centres/boats can only fill a 300 bar cylinder to 232 bar (therefore why have the extra weight of ther 300 bar cylinder)
Thank you and goodnight
Sid