Our A621 is a very popular stock housing or pressure vessel, and is ideal for small diameter equipment.  It is rated to 2,100m and has a fixed Packaging ID of 5.82'' (approx 148mm).  The standard lengths are 12,18 and 24'' (304.8mm - 457.2mm - 609.6mm) but we stock the raw tube material so they can quickly be made in almost any length. The housing can be fitted with a conical frustum Acrylic window for use with camera's, lasers etc. or for applications where it is important to be able to see in or out of the enclosure.