4-Sided Core STOPS ALL Broadheads & Field Tips. GlenDel's core design has 4 sides with different vital positions. This prepares you for shooting deer that would be broadside quartering away and from a 20 ft tree stand at 20 yards. Open Layered Polyfusion Technology Easy Arrow Removal! Fusing the internal layers to the inner target wall results in more uniform layer compression which in turn means easier arrow removal. And easier arrow removal means less shooter fatigue which means you'll get more and better practice! Longer target life! PolyFusion(TM) also results in longer target life. Because the layers are fused in place they hold their position. Arrows find their way between layers. Previously when an arrow hit a layer head-on the layer would buckle. This resulted in layer damage that reduced target life. Replaceable insert for longer target life