Learn
Learn about the needle
Short videos and plain-English guides: how to use a 31G 5/16" syringe, how sizing works, and how to reconstitute step by step.
How to use it
Using a 31G 5/16" syringe
A 31G 5/16" (8 mm) syringe is made for subcutaneous injections — into the fat layer just under the skin, not the muscle. The technique in these videos is exactly what you use with ours: clean the site, insert at a steady 90° angle, push slowly, and dispose of the syringe in a sharps container.
Subcutaneous injection with an ultra-fine syringe
Open RN · WisTech Open
The full technique, start to finish — the same one you use with a 31G 5/16" syringe.
How to give yourself a subcutaneous injection
Veterans Health Administration
Site selection, pinching the skin, and angle — clear and beginner friendly.
How to use an ultra-fine syringe
Singapore General Hospital
A short refresher on drawing your dose and clearing air bubbles.
Sizing
Gauge and length, explained
Gauge is thickness — and it runs backwards. The higher the number, the thinner the needle. At 31G, ours is up to 40% thinner than a standard 27G.
Length is depth. Our 5/16" (8 mm) length is the size most clinicians recommend for subcutaneous injections: short enough to stay comfortable, long enough to be accurate.
Gauge — how thin the needle is
- 31GPepprep0.25 mmBarely felt
- 30G0.30 mmLight pinch
- 29G0.33 mmNoticeable
- 27G0.41 mmSharp pinch
Higher gauge = thinner needle. At 31G, Pepprep is up to 40% thinner than a standard 27G needle.
Length — how deep it goes
- 5/16" (8 mm)Subcutaneous, most adults
- 1/2" (12.7 mm)Deeper subcutaneous
- 1" (25 mm)Intramuscular
Our 5/16" (8 mm) length is the size most clinicians recommend for subcutaneous injections — short enough to stay comfortable, long enough to be accurate.
How to
How to reconstitute, step by step
Reconstituting simply means adding liquid to a freeze-dried powder so it can be measured and drawn. The whole job is about being clean and being gentle: run the water down the vial wall, swirl rather than shake, and let the solution settle until it's completely clear before you draw.
How to reconstitute peptides
Peptide Pure
Bacteriostatic water down the vial wall, gentle swirl, no shaking.
The best way to reconstitute 10 mg peptides
The Peptide Couple
Walks through measuring water for a common 10 mg vial.
Peptide reconstitution instructions
Movement Clinic
A clinic-style demo of the same steps with sterile technique.
- 1Wash your hands and lay out a clean surface: your vial, bacteriostatic water, alcohol wipes and a fresh Pepprep syringe.
- 2Wipe the top of both the powder vial and the water vial with a fresh alcohol swab and let them air dry.
- 3Draw your measured amount of bacteriostatic water into the syringe, keeping the needle away from any surface.
- 4Insert the needle at a slight angle and let the water run slowly down the inside wall of the vial — never spray it directly onto the powder.
- 5Swirl gently until the solution is clear. Never shake: shaking can damage delicate compounds and creates foam.
- 6Label the vial with the date and concentration, store as directed, and dispose of the used syringe in a sharps container.
Why ours
What makes our needles amazing
- 31G ultra-fine — up to 40% thinner than a standard 27G
- Tri-bevel silicone-coated tip glides in with barely a pinch
- 5/16" (8 mm) length clinicians recommend for subcutaneous use
- Sterile, individually sealed, single-use — never reprocessed
- Batch-tested for burr-free tips and consistent flow
- Clear pack labelling so you always grab the right size
FAQ
Common questions
Ready for a needle you barely feel?
31G · 5/16" (8 mm) ultra-fine syringes, sterile and single-use, with better pricing on bigger packs.
- Sterile & single-use
- Free shipping over $35
- Ships from the US