Filled. Muay thai punching bag Made of top quality 22oz heavy duty polyester coated vinyl material, this material is more durable than genuine leather. These bags are hanging in North American gyms for more than 10 years and still holding up, Excellent quality product Triple stitched with heavy duty 6-ply twisted polyester thread Metal D-Rings - High Quality- Welded Steel D-Rings. Also comes with Heavy Duty heavy bag chain and swivel Leather reinforcement inside where each D-Ring is attached This heavy bag does not come with cheap zipper closure on top, It has Unique lace-up closing system on top of the bag which is durable than any other heavy bags available on the market, so no worry of RING TO CAGE branded punching bag to be popped from top as it does not come with any zipper closure. so you can also use this bag as a ground and pound dummy bag for MMA training You can fill between 100 to 125 LBS and measures 14” x 68”