I have two different brands of BCD jackets and both have grommets in the pockets for the attachment of a dive knife. My question is how do you attach the sheath to the grommets? Even with a dive knife of the same brand as the jacket {with the grommets} I don't see any provision or design on the sheath to allow this. Bought them both new, read and saw the company remarking on the grommets for dive knife attachment, but they offer no specific instructions to attach. I can call them, but I figured I would just try here first. Both jackets appear to have about a 3 3/4" spacing on the grommets, so it seems like they arrived at that figure to fit something. I have looked at the knives and sheaths offered by both brands that make the jackets and there is nothing I can see to coincide with the grommets.....I have to be missing something, two different manufacturers could not have picked the same spacing measurement out of the air and be coincidentally the same, claim it is for the purpose of attaching a dive knife and then not bother to make a knife that has any provision to attach it????? Thanks in advance for reading this and as always any information is greatly appreciated.