Abstract Confined coupled acoustic line-modes supported by two parallel lines of periodic holes on opposite surfaces of a glide-symmetric waveguide have a hybrid character combining symmetric and anti-symmetric properties. These hybrid coupled acoustic line-modes have a near constant group velocity over a broad frequency range as no band gap is formed at the first Brillouin zone bound... https://safeersappliancers.shop/product-category/neff-u2acm7hn0b-n50-built-in-59cm-a-b-electric-double-oven-stainless-steel/