We request 4 days to collect high-resolution structural high-pressure data on two zeolites - zeolite A and EMC-2. Our previous theoretical findings from geometric simulation showed that both zeolites possess a flexibility window, a property common to all real zeolites. The flexibility window is a range of densities over which the primary building units of a framework can be made geometrically stress-free. In a series of recent theoretical and experimental studies we have shown that the geometric property of the flexibility window is closely linked to the physical properties of the framework under compression. LTA has been studied under pressure before, so some spectroscopic data is available, but there is no structural data under pressure for either of these two zeolites.