The multilayer body (94) is secured within the space (102), preferably by vibration absorbing elements, more preferably by elastomeric O-rings or gaskets 104 formed of a material such as a fluoroelastomer, most preferably VITON (such as grade E60C, available from DuPont de Nemours & Co., Wilmington, Del.), FLUOREL (such as grade 2141), or KEL-F (the latter two both available from 3M Company, St. P