the two components it is preferred to use a version of the thiokol rlp composition liquid polysulfide elastomeric containing flame extinguishing chemicals obviously for roofing this is a desired feature the invention will be further described in connection with the following examples which are set forth for purposes of illustration only and in which proportions by weight stated to the contrary eleven samples 12 inch by 12 inch in size and in accord with the present invention were prepared as discussed below and tested for impact resistance resistance to degradation by elements and resistance to degradation by continual immersion in water commercially available shingles were tested as to impact resistance the test results are set forth in table ii below the samples of the present invention were made as follows i crumb rubber mats of various thickness and porosity density were coated with an elastomeric polysulfide composite of various thickness and with an elastomeric polysulfide rubber alone ii the elastomeric polysulfide composites consisted of a liquid polysulfide rubber and crumb rubber particles of various mesh sizes in various percentages by volume iii with some samples crumb rubber particles of various sizes were sprinkled onto and pressed into the elastomeric polysulfide composite layer iv the composite was allowed to cure at ambient temperature and the shingles then tested the particulars of each shingle of the present invention are set forth in table i below table i__________________________________________________________________________mat polysulfide compositeexampleporosity thickness polysulfide crumb rubber amp no mesh size inches type by vol particle size by vol __________________________________________________________________________1 buffings 40 80 1 8 34 to 1 4 34 a 50 20 to 60 50 2 buffings 40 80 1 8 34 to 1 4 34 a amp b 50 20.