as far as one can see that destructively here paracord was used with seven cores. It is thus possible (min.) use the seven times the length, if one divides the string. the supplied shackle (stainless steel, 5mm) I find a little too big. I'm going to try a 4mm. the breaking load of such shackles is anyway far to settle above the string-carrying capacity (approx 800kg at 4mm and 5mm at 1000kg). Oh ... fiddly the first time, agrees. I pushed through a pen and the end widened a little. then super easy to put on.
Update: a straight shackle M4 is actually a little small. fit, but does not look good. I have now decided to go for a round shackle M4.