Re. post#7 do you have the wonderjock or boosterjock?
Your image link includes bjk which suggests booster.
Whatever it is other guys have had problems of how to
wear and undesirably filling up with sand.
See questions and answers here and check which might
apply to assist in your dilemma:
http://www.thespeedoforum.com/viewtopic.php?f=8&t=14144