Traditional Bonnell Spring Construction. Sleep in comfort and awake refreshed with the Spine-Lab 5-Zone Bonnell Spring Mattress. – Mattress Depth: 21cm. The 5-zone design of the mattress provides both pressure-relief and support.

Traditional Bonnell Spring Construction. Sleep in comfort and awake refreshed with the Spine-Lab 5-Zone Bonnell Spring Mattress. – Mattress Depth: 21cm. The 5-zone design of the mattress provides both pressure-relief and support.