A protein complex found in the axoneme of eukaryotic cilia and flagella. It forms interconnections between the microtubule outer doublets that surround the inner central pair of microtubules. [ http://www.ncbi.nlm.nih.gov/pubmed/9295136 https://www.worldcat.org/search?q=bn%3A0198506732 http://www.ncbi.nlm.nih.gov/pubmed/21586547 http://www.ncbi.nlm.nih.gov/pubmed/22683354 http://www.ncbi.nlm.nih.gov/pubmed/21728999 ]