Dive canisters are available for some PLBs. McMurdo makes one and ACR is planning to offer one with their latest PLB. Technically, an Otter Box is rated for 100 ft, as I recall, That may suffice for typical recreational diving, but I am not sure I'd bet my life on that. Typical dive canisters are rated for much deeper. The McMurdo is rated to 450 ft. giving plenty of safety margin.
Fastfind, Fastfind Plus and FastFind Max G PLBsThe
McMurdo PLB Dive Canister Page says their aluminum canister is designed (and tested) to protect the McMurdo Fastfind PLB down to 150 meter (500 ft / 15 atmospheres) depth , so it certainly does seem like a good choice for a diver with the larger versions of the McMurdo Fastfind PLB, but if you have the smaller 200/210 model, see the PVC model below. It took me a while to find
the McMurdo Fast Find PLB Dive Canister manual. This page says it will also hold the GME MT410/MT410G but not the KANNAD and ACR PLBs.
The
Landfall Page says it is designed for the Fastfind, Fastfind Plus and FastFind Max G PLBs, and is slightly cheaper than the PLB itself.
This page has what seems to be the same unit (same 150m depth cite), though they call it a "Revere(R) Dive Canister, with some larger images of the unit, a slightly lower price, and says the unit is 6.5"x3.75"diameter, adds 1 lb positive buoyancy.
This vendor cautions that the Fastfind PLB must have the -20deg C battery, and
this page is more specific about the " -20 deg C Non Hazardous Lithium Battery".
This site has a nice photo I didn't see at the other sites, and also mentions the battery compatibility issue.
Fast Find 200/210McMurdo recommends a cheaper canister for the smaller Fast Find 200/210 ( the 210 is the new lightweight unit Doug Ritter reviewed
here ) which is "depth rated to 180 metres", is PVC rather than aluminum, and positive buoyancy with the PLB in it, which seems like a nice feature. I'd prefer a more visible color than black - preferably retroreflective so I can locate it with a flashlight at night or signal mirror by day, but some SOLAS retroreflective tape around the unit might address that. This
McMurdo page says that unit is only available from
Custom Divers. It is also a lot cheaper - the equivalent of $113 vs the $286 street price for the McMurdo canister. They also sell
replacement O-rings and suggest you change them each season.
The
McMurdo Fast Find 210 web page has a link to download the manual, and shows both the aluminum and PVC canisters on its
accessories page.