Pen models
In an effort to simplify the selection process and eliminate confusion around inconsistent version naming across the market, this page explains what V1 and V2 actually mean, what to consider when choosing a pen, and what Pen-Depot carries.
On this page
Pen body style and material
The pen body is what you hold. Two body styles are available, and the right choice comes down to hand size and personal preference.
Traditional body
Slimline body
Material
All Pen-Depot Research Injection Pens are built from premium aluminum — in every model and every color we carry. Aluminum provides superior durability, a more refined feel in hand, and better long-term wear. It also maintains its finish and structural integrity through repeated use and cleaning, making it the right material choice for a device that becomes part of your daily research protocol.
Pen cap style — V1 and V2
The cap style is what the version number refers to. There are two cap types and two cap types only.
Solid cap
A traditional solid closure that seals the pen completely, creating a protected environment for the cartridge between uses.
InjectThru cap
Features a retractable ring with a concealed opening that keeps the needle out of sight during administration — designed for researchers with needle apprehension.
You may see other sellers using V3, V4, or higher numbers. These are simply names used to describe a particular combination of body style, dosing capacity, and cap style — not a separate standard or additional designation. Once you understand the three decisions below, any version number you encounter will be easy to decode.
Three questions to ask yourself
1. Which body style suits you?
The Traditional body (6.5" × .75") is wider and shorter — a familiar pen feel that suits larger hands. The Slimline body (7" × .5") is longer and narrower — easier for smaller hands to grip and more discreet to carry. Both are aluminum.
2. How many units does your protocol require?
Both body styles are available in 60 unit and 80 unit dosing capacities. All Pen-Depot Research Injection Pens are calibrated at 0.01 mL per unit — the same as a standard insulin syringe. If your doses run toward the higher end, the 80 unit gives you more flexibility per cartridge.
3. Do you need the InjectThru cap?
If needle visibility is not a concern, the V1 solid cap is the straightforward choice. If you prefer not to see the needle during administration, the V2 InjectThru cap keeps it concealed. Note: the InjectThru opening is sized for standard insulin pen tips — confirm tip compatibility before ordering.
What Pen-Depot stocks
We carry two models, available in multiple colors. Both are premium aluminum construction.
Axis
Available in multiple colors
Marquee
Available in multiple colors
Not sure which pen is right for your protocol? info@pen-depot.com · +1-267-737-8433