The housing can be of any shape such as tubular, bowl...http://www.google.ca/patents/US7114834?utm_source=gb-gplus-sharePatent US7114834 - LED lighting apparatusAdvanced Patent SearchPublication numberUS7114834 B2Publication typeGrantApplication numberUS 10/668,905Publication date3 Oct 2006Filing date23 Sep 2003Priority date23 Sep 2002Fee statusPaidAlso published asUS7759876, US20040156199, US2007