31G is the ultra-fine end of the practical needle-gauge range — what GLP-1 pens (Mounjaro, Ozempic, Wegovy) ship with, and what most people switch to when they have been on weekly injections long enough to value comfort over draw-up speed. This site collects what we have learned about 31-gauge pen needles and syringes from running an EU supplier: what 4 mm vs 5 mm vs 6 mm actually changes, how to spot a counterfeit pen needle, and the rotation pattern that keeps a year on a GLP-1 from leaving your skin like a pin cushion.
We do not sell anything here. The articles below are the notes we send first-time GLP-1 buyers when they email asking which pen needle to order. If you decide a 31G is what you want, you can pick up a sterile pack at injectkit.com — but read the technique pages first. The needle is rarely the bottleneck; the angle, the speed and the spot are.
For thicker oils where 31G will clog or bend, see our sister site 29-g.com. For the all-rounder gauge, see 30-g.com.
Practical, source-cited writing on 31G pen needles and syringes — from the team that ships them across the EU.
Subcutaneous injection
The three subcutaneous injection sites — abdomen, outer thigh, upper arm — compared on absorption speed, comfort, ease of self-injection, and lipohypertrophy risk.…
Read article
Glp 1
Mounjaro, Wegovy and Ozempic needle and syringe sizes — practical UK guidance on gauge, length and travel kit options for GLP-1 self-injection.
Read article
Glp 1
4 mm is the modern default for GLP-1 self-injection. 5 mm is fine. 6 mm and 8 mm are mostly leftover diabetes-era stock. Here's what the FITTER consensus and EMA…
Read article
Mounjaro
Step-by-step Mounjaro KwikPen injection protocol from the Eli Lilly user manual, with the bits where first-time UK users actually get stuck.
Read article
Mounjaro
What pen needles fit the Mounjaro KwikPen, what UK pharmacies actually charge, and what Lilly's instructions require. 4 mm × 31G or 32G is the modern default.
Read article
Glp 1
Lipohypertrophy is rare on weekly GLP-1 injection but not zero. Here's a simple 4-week abdomen-and-thigh rotation pattern, with the FITTER guidance behind it.
Read articleIf you decide 31G is the right gauge for your routine, our sister shop sends sterile, individually-blistered pen needles and syringes from Spain across the EU and UK. Free shipping over €50.
Imogen Whitcombe
Editor · 31-g.com
31-g.com is the content arm of InjectKit, an EU sterile-syringe supplier operated by meeco Servicios Globales S.L. (CIF B42774703, Alicante, Spain). Articles are written by people who handle these syringes daily — and reviewed against the manufacturer's IFU before publication.
If you spot something wrong in an article, email [email protected] and a human will read it. See our editorial policy for the full version.
Alles wat u wilt weten voordat u bestelt.
31 gauge is de dunste precisienaald die commercieel verkrijgbaar is — ideaal voor precieze persoonlijk gebruik met minimaal ongemak. Als uw recept een andere maat aangeeft, volg dan het advies van uw arts. Voor 29G of 30G, bezoek 29-g.com of 30-g.com.
Bestellingen worden vanuit Spanje verzonden en komen in 2-3 werkdagen aan in de meeste EU-landen. Het tracking-nummer komt per e-mail zodra het pakket is verzonden.
Neutrale gewatteerde envelop. De afzender verschijnt als meeco SL, zonder productnamen, medische termen of merkzichtbare tekens aan de buitenkant. Alleen u weet wat erin zit.
Ongeopende, verzegelde verpakkingen kunnen binnen 14 dagen na levering worden geretourneerd voor een volledige terugbetaling. Om hygiënische redenen accepteren we geen geopende pakketten. E-mail [email protected] om een retour te starten.
Ja. Onze spuiten zijn kwaliteitsgeteste benodigdheden conform de EU-verordening benodigdheden (MDR 2017/745). Gesteriliseerd met ethyleenoxide en afzonderlijk verpakt. Elke partij is traceerbaar tot de productielocatie.
Ja. Wij leveren in alle EU-lidstaten plus Zwitserland, Noorwegen en het Verenigd Koninkrijk. Levertijden buiten de EU kunnen iets langer zijn (3–7 werkdagen) en invoerrechten kunnen van toepassing zijn.