Made to Fit.
Designed to Function.
A flexible protective sleeve built to help keep the battery attached and protect your device when dropped. Design yours below — custom name, logo, or artwork, rendered live before you order.
Custom text included — no upcharge. See real prints ↓
Protection That Stays Together.
The flexible outer sleeve holds the separate sections of your device together, helping prevent the battery from disconnecting and hitting the ground during a drop — while protecting the whole thing from everyday scuffs.
Built around the drop, not just the shelf
Most sleeves are cosmetic. This one is structural — a snug, flexible fit that keeps the pieces of your device acting as one unit instead of coming apart on impact, and still leaves full access to the controls, display, airflow, and charging port.
Ones we've already printed.
Real prints, real customers. Every one of these started as a name typed into that box up there.
Want yours on this shelf? Tag @designmainline when it lands.
Make It Yours.
Choose from available designs, or customize your sleeve with:
- Your name
- Shop logo
- Original artwork
- Raised graphics
- Custom colors
- Shop-exclusive designs
For shops & teams
Retail partners can stock ready-made designs or run an exclusive batch featuring their own shop logo and colors — something customers can't get in the original box.
Email jason@designmainline.com with what you're picturing. We respond within 24 hours.
Built like a part, not a trinket.
Printed at 0.12mm layer height so the text reads clean and the surface doesn't feel like a prototype.
| Material | PLA+ Tougher and less brittle than standard PLA |
|---|---|
| Layer Height | 0.12 mm Fine detail — text edges stay sharp |
| Wall Thickness | 1.6 mm Four perimeters, no flex or creak |
| Infill | 25% gyroid Impact resistance without the weight |
| Text | Raised emboss Printed into the part, not a sticker — it can't peel |
| Max Characters | 14 Longer text auto-scales down to fit the face |
| Print Time | ~2.5 hours Each sleeve printed individually |
| Turnaround | 3–5 business days Printed after you order — nothing sits in a bin |
Living with it
- Wipe with a dry or slightly damp cloth. Skip solvents and alcohol wipes — they'll dull the finish.
- Keep it out of a hot car. PLA+ softens around 60 °C / 140 °F, and a dashboard in July beats that.
- Friction fit — it slides on and stays on. No adhesive, nothing to peel.
- Scuffed it? Reorder the same design for less. Just reply to your order email.
Fitment: sleeves are modeled per device. Pick your model at checkout. Device brand names are used only to describe compatibility — Design Mainline is an independent maker and is not affiliated with, endorsed by, or sponsored by any device manufacturer.
Three steps. No back-and-forth.
Design it live
Type your text, pick your colors and finish. What renders on screen is what gets printed — no mockup emails, no waiting on a proof.
We print it
Your sleeve goes on the plate the same day it's ordered. Printed alone at 0.12mm, then hand-checked before it's packed.
It shows up
Boxed and shipped in 3–5 business days with tracking. Slide it on and you're done.
Before you order.
Will it fit my device?
How long can my text be?
Can I put a logo or artwork on it?
Is the text going to wear off?
What if I don't like it?
Can I order a bunch?
Make it yours.
Type a name, pick a color, then hit Order — we'll confirm your device model and send a payment link. Shipped in 3–5 days.
Design Your SleeveBuilt by Design Mainline
Mainline Sleeves is made by Design Mainline LLC — a technology studio in Southern California doing smart environment design, custom software, and physical products. Same hands, same standard.