This Deep Sleep Bonnell spring mattress will fit well on your single-sized bed. Made to offer medium-level comfort to the sleeper, the mattress has a knitted texture and will ensure a relaxed disposition throughout. Spot-clean it for maintenance. A Bonnell spring mattress is a traditional innerspring mattress that features interconnected hourglass-shaped steel springs. These springs are arranged in a grid pattern and connected by wire at the top and bottom. Bonnell spring mattresses provide good support and durability and are generally less expensive than other types of innerspring mattresses. However, they are not as responsive to body contours as some of the more advanced innerspring and foam mattresses, and may not provide as much pressure relief for people with aches and pains.