Vinyl Weight Plate 30/31 mmVinyl Weight Plates 30 31 mm: Time to Tackle the Weights The 1. 25 kg, 2. 5 kg, 5 kg, 7. 5 kg, 10 kg to 15 kg plastic weight plate is the entry level weight for beginners. It is ideal for targeted training of various muscle groups, such as the biceps. The robust and floor friendly plastic dumbbells are available in different versions. Universal & standard compatibility: With a hole diameter of 30 31 mm, they are suitable for all dumbbell and barbell