Amazon.com: GoHobby 1.9 Tire Foam RC Crawler 1.9 Dual Stage Foam Inserts for Axial SCX10 90046 TRX4 Rock Crawler 1.9 Inch Wheel Tires, Set of 4 : Toys & Games
Video #7 Installing Dual Stage Foam in Hyrax Tires - YouTube
Dual stage foam for you to make filters to your own pattern.