Easy to put on & Adjustable] : This dog harness is easy to put on and take off with 4 buckles . You can adjust the elasticity with the four-way adjustment straps on the neck and chest. [Anti Pull Dog Harness] : Our Tactical Dog Harness has 2 D-shaped rings on the chest and back. Once your dog rushes forward, you can pull the front ring to control it. When you walk with your dog, the ring on the back provides less stress on its neck. [Size Guide] : Size XL:chest circumference: 66-107cm, neck circumference: 51.79cm, belly length: 33.5cm, back length: 23.5cmSize L: chest circumference: 61-94cm, neck circumference: 46-74cm, belly length: 30.5cm, back length: 21.2cm. Size M: chest circumference:56-84cm, neck circumference:41-56cm, belly length: 26.5cm, back length: 18.5cm. Size S: chest circumference:51-79cm, neck circumference: 36-53cm, belly length: 21.5cm, back length:16.5cm. Please measure your dog's neck and chest circumference to match the appropriate size. If you have any questions about sizing, please do not hesitate to contact us. [Durable & Comfortable] : The sandwich mesh lining is breathable and refreshing. The durable outer layer of the dog harness, made of durable oxford material, does not scratch easily, is long lasting and easy to clean. [System Molle & Tactical ] : Our dog harness is equipped with a tactical Molle system so you can hook the hitching hooks to carry light objects. You can also decorate your dog by attaching a custom sticker to the hook and loop panel on the back. AUROTH Your Trusted Source For Pet Supplies Please measure the circumference of your dog's chest and neck before purchasing the product. Here's our size board. Step 1: START TO WEAR Unbuckled and release the straps and slide it over the dog's head. Step 2: POSITION 1. Arrange the bottom strap between the front legs. 2. Fasten the quick release buckles.adjust the straps' distance. Step 3: ADJUSTABLE 1 .Sometimes you may need to pass the adjusting point through the padding. 2.The upper strap should be parallel to the Lower strap.