The york 15kg cast iron dumbbell set is designed to provide challenging comfortable and safe workouts the set is comprised of 8 x 125kg weights 4 x 05kg weights and 2 spinlock dumbbell bars with 4 grey vinyl spinlock collars which together weigh 3kg this lets you to adjust the weight you wish to lift up to a maximum of two 75kg dumbbells the bars have knurled black nylon hand sleeves that are crafted to deliver an optimum fit and heavy duty threaded ends for the 4 spinlock collars the