strip acoustic decorative. metal suspended ceiling. CRA. Width: 140, 190, 290 mm. Length: 2,500 mm. Stable and sturdy, Atena CRA staves with 140, 190 and 290 mm width, up to a maximum of 2.5 m in length, can be installed by simply laying on the perimeter frame, completing Atena's range of self-supporting narrow base staves.