Experience restorative sleep with a king-size gel-enhanced bonnell spring mattress for back support that brings together cooling comfort and orthopaedic reliability. A 12.5g open coil Bonnell spring system helps encourage better spinal alignment and reduces pressure on joints and muscles, while the innovative gel layer contours to your shape and regulates temperature for a consistently cool night's rest. Finished with a breathable quilted fabric and recycled polyester comfort layers, this 5ft bonnell spring mattress with cooling gel layer offers a soft to medium firmness and is rolled and boxed for convenience-making it a smart choice for modern bedrooms seeking comfort, support and sustainability.