ISC Klick Buckles are tested without webbing, in a straight-line (direct) pull, as required for the stringent ANSI Standard. This method gives an accurate and genuine measure of strength, as the entire test load is put through the buckle itself (rather than the load being shared between the buckle and the webbing). Our Klick-lock buckles are amongst the strongest available on the market. ISC Klick-lock Buckles are fitted with a double-button tang retention mechanism, which will only disengage to release the tang when both buttons are pressed simultaneously. The retention mechanism will not disengage under load.