This domains has an immunoglobulin like beta sandwich fold. It is found in the FlgD protein the flagellar hook capping protein. THe structure for this domain shows that it is inserted within a TUDOR like beta barrel domain [1].

1: Crystal structure of the C-terminal domain of a flagellar hook-capping protein from Xanthomonas campestris. Kuo WT, Chin KH, Lo WT, Wang AH, Chou SH; J Mol Biol. 2008;381:189-199. PMID:18599076