Walk into any tattoo supply room and you will see boxes labeled 1207RL, 1009M1, or 0814RS. To a new artist these look like random part numbers. To us they are a language. Every digit and letter tells you how the needle will behave in the skin. Pick the wrong size and the line blows out. Pick the right one and the ink sits exactly where you want it (more on that here: how to choose the right size). At R&G Bio we have made tattoo needle cartridges since 2009, so we have seen every mismatch you can imagine. This guide breaks the size chart down in plain words, so you can read any box like a pro.
Why Size Matters More Than Brand
People often think expensive needles guarantee good results. Not true. A correctly sized mid-range cartridge beats a mismatched premium one every time. Fine-line work with a #12 gauge means fighting the needle’s own thickness. Shading a big portrait with a 3RL means torturing the skin. Size controls ink flow, depth, trauma, and healing. Learn the numbers first. Worry about brand later.
⚠️ Reality Check: In our ISO 13485 facility, we reject batches when the gauge is off by just 0.01mm. That tiny difference changes how the needle feels in the hand and how it heals in the skin. Precision is not marketing talk. It is physics.
How to Read a Cartridge Code
We use the industry-standard naming system, same as most professional makers. Once you know it, one glance at a code tells you exactly what is inside. Take 1207RL as an example.
1207RL = 12 (Gauge) + 07 (Needle Count) + RL (Configuration)
The first two digits are the gauge, the needle diameter. The middle digits are the count, how many needles sit in the cluster. The letters at the end are the configuration, how those needles are arranged. Every professional maker uses this system, including us. You can see it across our whole RGBIO tattoo needle cartridge catalog.
Gauge: The Diameter of the Wire
Gauge is the thickness of each individual needle. We make three standard gauges. #08 is about 0.25mm. #10 is about 0.30mm. #12 is about 0.35mm. A small difference on paper, a big difference in the skin. A #08 goes in with almost no resistance and leaves a hair-thin line. A #12 carries more ink and leaves a bolder mark. Most artists keep all three and pick per job.
Needle Count: How Many Points Touch the Skin
The count is how many needles are grouped together. A 01RL is a single needle. A 14RL has fourteen in a tight circle. Higher counts give thicker lines and more ink. Lower counts give precision and less trauma. Our standard range runs from 01 to 27, which covers everything from single-needle realism to fast color packing.
Configuration: The Shape of the Cluster
The letters are where the function lives. RL means the needles form a circle that comes to one point. That is for lines. RS is the same circle but looser, so the points spread a little. That is for shading and soft edges. M1 is a flat double row, made for filling solid areas fast. RM is the same flat row bent into a curve, so it follows the skin and blends smoother. Each one has its job. Swapping them around is a recipe for bad work.
💡 Pro Tip for Buyers
When you are ordering wholesale, always ask for samples across all three gauges and at least four configurations. Test them on practice skin before you commit to a bulk order. Any serious distributor does this, and any serious maker will say yes.
The Gauge Breakdown: #08, #10, and #12
Gauge is the most important number on the box. It controls precision, trauma, and ink load. At our factory in China, we check the diameter of every spool of 316L surgical stainless steel before it goes near the production line. Here is what each gauge does in the skin.
#08 (Bugpin): 0.25mm — Precision Work
Bugpins are the thinnest standard gauge. They go in with almost no resistance and leave a very small channel, which makes them ideal for fine-line tattoos, portrait details, and soft gradients. The trade-off is speed. A Bugpin carries less ink per pass, so you need more passes to build density, plus a slightly higher voltage to make up for the lighter needle. For our Bugpin tattoo needle cartridges we run extra quality checks, because thinner wire bends more easily during assembly.
#10 (Double Zero): 0.30mm — The All-Rounder
Walk into a busy shop and look at what the resident artist is using. Odds are it is a #10. This gauge sits right in the middle: thin enough for detail, thick enough to carry ink. Lining, shading, and everything in between. Our #10 series is the highest-volume line in our wholesale orders, because distributors know it is the safest bet for most artists.
#12 (Standard): 0.35mm — Bold and Fast
The workhorse. Traditional styles, tribal work, anything that needs thick, saturated lines. The 0.35mm wire carries more ink and goes in with authority. It takes a confident hand, because mistakes are harder to hide. Most of our #12 demand comes from shops doing American and Japanese traditional. More ink per pass means fewer passes, and less trauma on large fills.
Configuration Guide: RL, RS, M1, and RM Explained
Configuration is the shape of the needle cluster. It is the difference between drawing a line and painting a surface. Here is what each type does, and what we make.
The curved magnum deserves a special mention. For three years running, it has been the most requested configuration in our wholesale catalog. The curved edge gets rid of the hard lines a flat magnum can leave at the border of a shaded area. For photorealistic portraits and smooth gradients, the RM is essential. We make Curved Magnum tattoo cartridges in #10 and #12, with counts from 5 to 27 needles.
💡 Stocking Tip for Distributors
If you are building inventory for a new shop or channel, start with the 80/20 rule. Go heavy on #10 RL and #10 RM in counts 05, 07, and 09. These six SKUs cover most daily tattoo work. Then add #12 magnums for traditional artists and #08 bugpins for fine-line specialists.
Taper: The Hidden Spec That Controls Ink Flow
Beginner guides rarely talk about taper, but it controls how much ink enters the skin with each puncture. Taper is how long the needle takes to come to a point. Longer means sharper and narrower. Shorter means blunter and wider. It changes trauma, saturation, and line precision.
Our standard liners ship with long taper by default. Shaders and magnums ship with medium taper. Super long taper is available on request for OEM clients building realism product lines. If you serve high-end portrait artists, an SLT variant in your private label line is a smart way to stand out.
Style-Specific Selection Guide
Theory is nice, but artists need practical answers. Here is what we tell the distributors who buy from us, based on the styles their artist clients do most.
What Makes RGBIO Cartridges Different
We do not just stamp codes on generic needles. Every cartridge that leaves our factory comes from controlled production, medical-grade materials, and full documentation. Here is what that means in practice.
Medical-Grade Materials and Cleanroom Production
Our needles are 316L surgical stainless steel, the same alloy used in implants. The housings are medical-grade polymer, not industrial plastic. Assembly happens in ISO Class 7 cleanrooms, and every batch is traceable from raw steel to sterilization. We hold ISO 13485, CE Mark, FDA registration, and KFDA approval. For distributors this paperwork matters. It lets you sell into regulated markets without compliance headaches.
Membrane System for Cross-Contamination Prevention
Every RGBIO cartridge has a silicone membrane inside that blocks backflow. When the needle retracts, the membrane seals the ink path, so blood and pigment cannot travel into the machine grip. This is not an optional upgrade. It is standard on every SKU we make. For artists it means a clean machine. For distributors it means a product that meets modern safety expectations with no upsell.
Transparent Housing and Precision Fit
The tip of every RGBIO cartridge is transparent. This is not about looks. It lets the artist see ink flow and needle contact in real time. The housing-to-grip fit is molded to tight tolerances to kill wobble. A stable needle is a predictable needle. We test this on vibration rigs before any design goes into mass production.
OEM and Private Label Services
If you are a distributor or brand owner, we do full OEM/ODM. You can customize configurations, packaging, labeling, and even taper profiles. Minimum order starts at 20,000 units, which is within reach for mid-sized brands. We handle the compliance paperwork, sterilization validation, and batch traceability. You handle the brand. Our tattoo needle cartridge wholesale page has the full specification sheet.
Quick Reference: RGBIO Size Chart at a Glance
Print it, screenshot it, pin it to the shop wall. Here is the full RGBIO size chart at a glance.
Gauge: 08 (0.25mm) | 10 (0.30mm) | 12 (0.35mm)
Counts: 01 / 03 / 05 / 07 / 09 / 11 / 13 / 14 / 15 / 17 / 18 / 23 / 27
Types: RL (Round Liner) | RS (Round Shader) | M1 (Magnum) | RM (Round Magnum)
Combine any gauge with any count and any configuration to build the exact SKU you need. A #10 07RM is a curved magnum with seven 0.30mm needles. A #12 14RL is a round liner with fourteen 0.35mm needles. The system is modular, so our catalog covers hundreds of active SKUs without forcing anyone into configurations they do not want.
Get a Quote or Request Samples
If you are a distributor, shop owner, or brand manager looking for a cartridge manufacturer you can rely on, talk to us. R&G Bio makes wholesale tattoo needle cartridges with full regulatory documentation, OEM service, and fair pricing. We ship to over 50 countries and keep standard SKUs in stock for fast turnaround.
Final Word
A cartridge is a precision tool, and the code on the box is its recipe. Gauge controls thickness. Count controls coverage. Configuration controls function. When all three match the artist’s style, the work is predictable and the skin heals well. That is why we take the numbers so seriously. If you have a question about a specific SKU, or want to talk through a custom configuration for your brand, reach out to us. We answer within 24 hours.