Posted by Heather Wood, a PhD student studying bats at Stockholm University:
www.wildlabs.net/community/thread/554
Her junction box is from a Swedish company - Rutab - but similar IP66 boxes are available from the UK (including RS Components & eBay)
PS: IP66 = Dust Tight and protection against "Powerful Water Jets" - NOT immersion (that would be IPP67/68).
See https://en.wikipedia.org/wiki/IP_Code