Equilibrium used in our numerical simulations of standing sausage modes in curved coronal slabs. The line contours show the magnetic field lines. Top: the colour contours show the (logarithm of) density, which has an enhancement describing a curved field-aligned loop with density contrast ratio ρ₀/ρ_e = 50 and an aspect ratio of a/L = 0.12 at its apex. Bottom: the colour contours show the Alfvén speed which is constant inside and outside the loop.