Getting Started
Start here. It takes about two minutes.
New to refillable research pens? Most people are. The idea is simple: instead of drawing up a fresh syringe every session, you fill a sterile cartridge once, drop it in the pen, and from then on you just dial and dispense. This page covers everything worth knowing before your first use — what you need, what fits what, and the two or three things that trip people up on day one.
Use the menu on the left to jump straight to what you're after.
1. Before you begin
A MODTECH pen is hardware. It dispenses whatever you put in the cartridge — nothing is included, prefilled, or sold with it. That means the loading and reconstitution side is on you, and we assume you already have a working knowledge of it. Plenty of videos, blogs, and podcasts cover that ground in detail.
Your order arrives as hardware only. We don't include printed instructions with orders — this Help Center is the manual, so it's always current and we can fix or expand it the day someone asks a good question.
Do a practice run first
Use a non-active solution. Sterile water or saline is fine. Load it, dial it, dispense it, take the pen apart, put it back together. Ten minutes of practice is the difference between a smooth first session and a wasted one.
Please don't learn on your actual compound. MODTECH isn't responsible for material lost while you're getting the hang of the hardware.
See the full routine
If you want to watch the whole thing before you touch anything, the How It Works page has a video walkthrough from first fill to daily use.
Read the safety and warnings guidance before first use
2. What you'll need
- A pen. The V2 or the V3. Either one.
- Sterile 3mL glass cartridges. Sold in 10 and 20 packs, each one individually sealed. One cartridge covers many sessions.
- Pen tips. Sold separately. The pens accept standard universal screw-on pen needles. Use a fresh one every session.
- A syringe for the one-time fill, plus your reconstituted solution and alcohol wipes.
What you don't need
No adapters, no special tools, nothing to modify. The cartridge drops straight in.
Full cartridge information Choosing the right pen tips
3. Which pen to pick
Both pens work the same way and take the same cartridge. The difference is the finish.
| V2 | V3 | |
|---|---|---|
| Finish | Silver, blue, green, or gold | Matte black |
| Body | Solid machined aluminum | Solid machined aluminum |
| Dial | 60 click-stop increments | 60 click-stop increments |
| Cartridge | 3mL / 3cc glass | 3mL / 3cc glass |
| Tips | Universal pen needles | Universal pen needles |
Pick on color and price.
Already own a V1?
Your existing cartridges carry straight over. All three generations use the same one.
4. Specs at a glance
| Calibration | 0.01 mL per click — the same unit you'd read on a standard insulin syringe. |
| Dial | 60 click-stop increments. Each click is a fixed, repeatable step — you feel it rather than reading graduation marks, so the amount is identical every session. |
| Cartridge | 3mL / 3cc borosilicate glass with an 11mm long gray stopper. |
| Cross-compatibility | The same cartridge fits V1, V2, and V3. No adapters. |
| Sterility | MODTECH cartridges are steam sterilized and individually sealed in a CE/ISO 11607 certified pouch with a steam indicator. Intact seal means sterile. Open it right before use. |
| Tips | Standard universal screw-on pen needles, sold separately. Fresh tip each session. |
| Size & weight | 6.3 × 0.79 × 0.79 in, about 1.76 oz. |
| Storage | Built for the refrigerator with the cartridge loaded. It fits in the fridge door. |
What one click equals
Every MODTECH pen is calibrated at 0.01 mL per click. If you're used to an insulin syringe, that's exactly one unit per click — the numbers you already know carry straight over, no conversion.
The dial has 60 clicks, so the most it will dispense in a single turn is 0.6 mL. A full 3mL cartridge holds five of those.
Cartridge spec — read this before buying elsewhere
These pens take 3mL cartridges with an 11mm long stopper, and nothing else. If you're sourcing cartridges from another supplier, check that spec before you order. A short-stopper cartridge will not seat correctly.
Full cartridge information Compare pen models
5. Using the dial
Two things are worth knowing before you push on anything, because they're the most common reason a brand-new pen feels “broken.”
Let the plunger turn — don't force it
The plunger rides on a corkscrew thread. When you press it back into the body to reset it, it needs to rotate under your finger as it travels. Guide it gently and let it turn. Pushing it straight in with force will bend or break it, and that's not a warranty issue — it's avoidable.
It won't move without a cartridge in
The mechanism needs resistance to actuate. If you dial and press with an empty cartridge holder, nothing happens and the pen looks defective. It isn't. Seat a cartridge, then test.
New pen feels stiff?
That's normal on the first few cycles. Work it slowly a handful of times before your first real session — that's exactly what the practice run in step 1 is for.
Troubleshooting guide Loading and priming
6. Taking it apart
“Where's my cartridge holder?”
It's in there. Promise. The order of operations just isn't obvious the first time:
- Pull the pen apart first. Don't unscrew anything yet — pull straight, and the cap comes off to expose the cartridge holder.
- Then unscrew the cartridge holder from the pen body.
If you unscrewed it first by mistake, the cartridge holder is now hidden up inside the cap. No harm done — screw the pen back together, then start again from step 1.
Putting it back together
The threads on a new pen can be stiff and may need a little extra pressure to catch when you reattach the cartridge holder. That's normal and it loosens up with use. Start the thread straight and turn slowly so you don't cross-thread it.
Load a cartridge and prime Troubleshooting guide
7. Shipping
- Orders ship from Amazon's U.S. fulfillment centers.
- Processing: 1 to 2 business days.
- Delivery: 3 to 5 business days standard, or 1 to 2 business days with Buy with Prime.
Packaging & tracking
Tracking arrives by email automatically. Packaging is discreet — a standard Amazon box, with nothing on the outside indicating what's inside.
30-day guarantee
Everything is covered by our 30-day money-back guarantee.
Full shipping & guarantee details
8. Where to go next
- Compare pen models
- Load a cartridge and prime
- Cartridge information
- Choosing pen tips
- Troubleshooting
- Safety and warnings
- Full FAQ
Still stuck?
Email tfortech@modtechsupply.net. A real person answers within one business day, and that person is the owner.
MODTECH products are precision hardware sold for laboratory and research use only. They are not medical devices. No substances are included with or sold alongside any product, and nothing on this page constitutes medical advice or instructions for administering any substance to humans or animals.