Perth manufacturers customize stack heights from 50-200mm for casing sizes 4.5" to 9-5/8". In fracking applications, they endure 5000 psi differential without nibbling, extending packer life by 40%. Field trials in Santos wells show 98% integrity after 24 months, versus 70% for single seals. Local FEA modeling optimizes compression ratios 20-30% for thermal expansion matching. https://globalsealstech.com/product/seal-stack/