About the D'Addario DRGBK-VR200 Rosin Guard with Natural Light Rosin:
 
D'Addario's Rosin Guard helps players extend the life of their rosin by keeping it secure on all sides. The comfortable shock-absorbent grip allows for easy and effective application to the bow while the magnetic backing makes sure the Rosin Guard is always within reach. The guard protects rosin from breakage, extending the life of each rosin cake. It includes D'Addario Natural Light Rosin and can be refilled with any D'Addario Natural Rosin, as well as Clarity Rosin.