Don, I’m not sure what the compound is but they are  definitely harder than they probably were back in the day. The size is 10.00-15......which is 10” wide and about 29” tall.  
 
They fill out the wheel well very nice on my Chevelle. The picture below is with an 8” wide wheel....the picture above is with a 7”. 
 
Kurt
		 
		
		
		
			
		
		
		
		
		
		
			
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1969 SS396 Post Sedan Delivered to Van-T Topeka KS 
MCACN Day2 Concourse Gold Award
 
1965 VW El Lobo Dune Buggy built in the mid 70’s for the Iowa Shriners
 
1968 Schwinn Orange Krate  
1969 Schwinn Pea Picker   
1968 Schwinn 5-Speed  
1970 Schwinn 3-Speed Deluxe  
1972 Schwinn 10-Speed Continental  
1973 Schwinn 5-Speed Suburban  
All Original Paint Bikes
			  
		
		
		
		
		
			
			
			
		
			
			
			
			
			
			
			
			
			
				
			
			
			
		 
	
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