Enhance your spa experience with this premium quality, heat-retention hot tub cover, expertly designed to lock in warmth while keeping your water clean and protected. Featuring a floating inflatable bladder that fits neatly beneath your existing spa lid, it creates a powerful thermal barrier that helps maintain optimal water temperature, reduces heat loss, and lowers energy consumption. This innovative solution shields your spa from dirt, leaves, and debris, easing the workload on your filtration system and making maintenance effortless. Its robust inflatable construction not only boosts insulation performance but also encourages rainwater outflow. Designed for compatibility with Dellonda 4-6-person hot tub DL91, this heat retention cover is an ideal upgrade for hot tub owners who want greater efficiency, cleaner water, and extended hot tub longevity - all while enjoying consistently warm, relaxing soaks.• INFLATABLE HOT TUB - Heat retaining lid designed for 4-6-person spa pools to improve insulation and reduce heat loss when not in use.• HEAT RETAINING LID - Floating thermal layer sits directly on the water surface to maintain water temperature and lower energy use.• DEBRIS PROTECTION COVER - Prevents leaves, dirt and insects entering the water to keep your hot tub cleaner for longer.• THERMAL INSULATION BLADDER - Inflatable insert improves heat preservation while supporting rainwater runoff beneath the main cover.• PREMIUM QUALITY MATERIAL - Premium quality and durable construction ensure long lasting performance with minimal maintenance required.• SIZE AND COMPATIBILITY - Suitable for 4-6 person Dellonda hot tub DL91, with a Ø165cm.