Reliability: Placing the bow components in the correct position helps archers maintain the reliability of the bow components. Quality Materials: T Square Ruler is made of aluminum alloy. Nocking buckle pliers are made of stainless steel. String nocking points are made of brass. More Unique: Surface of the square T-ruler adopts epoxy paint technology, resistant to scratches, and features two measurement units in mm and inches. Nocking buckle pliers have a spring design and smooth jaw opening for easy use. Includes 8 nocking points with an inner layer made of anti-slip nylon to help secure and protect the bowstring. Widely Used: The kit can measure the height of the bracket, secure the position of the string nocking points, and ensure proper setup for common bow configurations. Specifications: Material: Metal Size: 12.9 x 3.46 Inch and 2.63 x 1.1 Inch / 2.67 x 1.4 Inch Color: Black Package Contents: 1 x T-shaped bow square 1 x nocking buckle pliers 8 x bowstring nocks set