Products by Crash Ratings Our anti-ram products are crash certified to the ASTM M-ratings which have replaced K-ratings. Both M-ratings and K-ratings use a 15,000 lb. vehicle for testing. The primary difference is that M-ratings are certified based on how far the payload travels past the barrier, while K-ratings are based on how far the front bumper travels past the barrier. Because of their similarities, we can offer equivalent M and K ratings. If a rating is engineered, it means that the product is certified by the ASTM based on an engineered configuration and computer model testing. We also offer products that are certified to interational standards like PAS 68 and IWA 14. Read our guide for more information on crash ratings and what they mean.