Last updated 17/09/2026
Pen guide
what you received
Select the pen or pens in your order. These are 60-unit pens — 1 unit is 0.01 ml (100 units per ml). The cartridge holds up to 3 ml.
- 10mg1 ml fill
- 20mg2 ml fill
- 30mg+3 ml fill
Your pens
Tap every compound you received. Full pens and refills use the same fill table.
Select a pen above to see fill volume, units, and the amount table.
Full pen
Pre-filled, and the reusable device is included. This is the starter if you do not already have a Zelopeps device.
Refill
The cartridge only. Keep the device you already have and swap the cartridge. Same fill as a full pen.
Empty device
The reusable pen on its own, under Supplies. Buy once. After that you only need refills.
How to use the device
- Attach a new sterile needle until it is tight. Keep the outer cap on until you are ready.
- Prime 1–2 units into a wipe the first time you use a new cartridge, so the fill reaches the needle.
- Dial the research volume from the table. One click is one unit. The dial goes to 60.
- Hold the button in until the dial returns to 0, then count to 6 before removing the needle.
- Unscrew the needle into a sharps bin. Recap the pen and put it back in the fridge.
Tips
- Do not add BAC water. Pens and refills arrive already reconstituted.
- Write the compound and size on the device if you have more than one.
- Keep unused pens cool, dry, and away from light. Do not freeze a filled cartridge.
- If the dial will not turn, you are at the end of the cartridge — swap to a refill.
Filled to order
We make each pen and refill after your payment clears, and before we dispatch. They are not stored pre-filled. Needles, wipes, and extra BAC water are separate shop items unless they were on the same order.
Order again or ask us
Refills and the empty device are in the shop. If a parcel arrives damaged, message us with photos.