Dispensing Pen Needles – 32G / 4MM – 50 Pack

32G x 4mm Dispensing Pen Needles (50-Pack) for Peptide Injector Pens

Signature Peptides Pen Needles are ultra-fine 32-gauge disposable dispensing tips designed specifically for use with reusable peptide injector pen systems. Each needle in this 50-pack is individually sealed in sterile packaging, features a universal screw-fit attachment and is intended for single use only.

At 32G (0.23mm outer diameter) and 4mm long, these are the thinnest pen needle option in the Signature Peptides range, engineered for comfortable, shallow subcutaneous delivery with minimal tissue disruption.

This 50-pack is the mid-range quantity option, sitting between the 20-pack for lighter use and the 100-pack for researchers running longer protocols. All three packs contain the same ISO-certified Pen Needles with identical specifications.

Product Specifications

Why 32G x 4mm for Peptide Pen Systems

The 32-gauge specification is one of the finest needle gauges available for pen injector devices. At just 0.23mm in outer diameter, these Pen Needles cause minimal tissue disruption during insertion, which matters for protocols that require daily or frequent use over several weeks. The silicone coating on each needle further reduces friction, allowing smoother penetration with less resistance at the point of entry.

The 4mm length is designed for shallow subcutaneous delivery. In research applications involving peptide solutions, subcutaneous administration into the fat layer just beneath the skin surface is the standard delivery route. A 4mm needle reaches this layer without the risk of accidental intramuscular injection, making it the preferred length for most users working with pen-based dispensing systems.

Universal Screw-Fit Compatibility

These Pen Needles use a standard universal screw-fit attachment that threads securely onto the needle end of any compatible injector pen. This includes the Signature Peptides Injector Pen Kit and all V1, V2 and V3 reusable pen systems widely used in the UK research market. The same thread design also fits pens from other manufacturers that follow the universal pen needle standard, so you won’t risk buying needles that don’t match your device.

How to Attach and Use?

Remove a single needle from its sealed packaging. Screw it onto the needle end of your loaded pen until it sits snugly. Remove the outer protective cap first, then the inner cap immediately before use. After delivering your dose, remove the used needle from the pen and dispose of it safely. Never reattach the inner cap to a used needle, and never leave a needle attached to the pen between sessions, as this can allow air into the cartridge and affect dose accuracy.

Single-Use Replacement Schedule

Every needle in this pack is intended for one use only. The ultra-fine 32G tip is engineered for a single clean puncture. After that first use, the tip loses sharpness, and the silicone coating degrades, increasing friction and discomfort on subsequent insertions. Reusing Pen Needles also introduces contamination risk from environmental exposure between sessions.

At one needle per session, this 50-pack provides enough supply for approximately 50 research sessions. For researchers using their pen daily, this covers roughly seven weeks of use. The 100-pack offers better long-term value for extended protocols.