I always use 29 G 1 ml syringes , i tried the 30/31 g half a ml short-tips once and was totally confused my ex-girlfriend berated me for being so foolish as o get short-tips although we were both skinny with bulging veins neither of us could register with those ridiculously short tips (and we both had very different techniques from almost 45 degree quick forcefull "jab" as compared to my technique which consists of slowly sliding the tip in as horizontally /parralel to the vein as possible .
anyways lately i have been using only 29 G 1 ml terumo's myjector (insulin fixed tip orange cap) the only difference with the BD's is the cap and that they are distributed for free at the needle exchange , also i noticed less defects with the myjector compared to the BD"s(read none but maybe there is some kind of quality control at the exchange although i'd doubt it) , the only disadvantage is that the BD seems to have a sharper point/ needle
The Terumpo Myjector 100 unit Insulin Syringe
for acidifying the bases (all the heroin here is in base form) , i usually use medical grade ascorbic acid from the exchange in emergency it's vinegar or anhydrous citrate from the chinese food store.
for cottons i use those ear cleaning sticks with the little piece of cotton q, never got cotton fever from iy yet they aren't sterile , i'd greatly prefer the "sterifilt" which iis widely available in france and luxembourg but not here unfortunately