The remains of a partly exploded steel cased munition. If the device had fully functioned the case would have been shattered into many high-velocity fragments.
<a rel="nofollow" class="external text" href="https://www.flickr.com/people/147447263@N02">Nick /</a> from United Kingdom
CC BY 2.0
<a rel="nofollow" class="external text" href="https://www.flickr.com/photos/intrepidexplorer82/50997124600/">Shrapnel</a>