Summary

If on HRT and supplementing Testosterone it can be more convenient to find insulin syringes which are typically 29g or 30g making it harder to draw the oil into the syringe. Rather than waiting a few minutes or messing around with backloading I have found this to be the most convenient way. I believe only the smaller vile will work with these so they are not exactly universal to any syringe or vile.

The newest model is for 0.5mL syringe (pictured in white). This one works the best.

The first design is for 1.0mL syringe (pictured in black).