Three Cartridge Types. One Device. These are replacement cartridges for the Dr. Pen A6 microneedling pen. Each cartridge is sterile, individually sealed, and designed for single use per session. Available in three configurations — 12-pin, 36-pin, and nano — to suit different areas and routines. Needles are stainless steel. We do not claim titanium — most cartridges at this price point are not, regardless of what other sellers say. ✓ Compatible with Dr. Pen A6 Only ✓ 12-Pin, 36-Pin & Nano Options ✓ Sterile Single-Use — Stainless Steel Needles ✓ No Serum Chamber — Stamping Only .tabs { margin-top: 20px; } .tab-label { cursor: pointer; font-weight: bold; padding: 10px; border-bottom: 1px solid #ccc; background: #f9f9f9; display: block; } .tab-content { display: none; padding: 10px 0; } input[type="checkbox"]:checked + .tab-label + .tab-content { display: block; }