FEIERDUN 2-in-1 adjustable dumbbells combine dumbbell and kettlebell functions, with 15 weight selections (2.5lb increments for 5-25lbs, 5lb increments for 25-52.5lbs) to suit beginners to pros for muscle sculpting and strengthening. Adjust weight in 1 second by twisting side dials for convenient, efficient workouts. Made of alloy steel with thermoplastic rubber, they’re durable, water-resistant and wear-resistant. The anti-slip handles (thicker middle, tapered ends) offer a secure grip. Space-saving (20.87" L x 12.6" W x 11.61" H) with a protective base to avoid floor damage, perfect for home gyms. Backed by a 1095-day warranty (free replacement parts for quality issues) and 12-hour customer service response.