Monolith XL / Shower Filtration
Shower inspring water.
Every shower filter makes the same promise. Monolith XL keeps it: six stages, 4× the media, zero plastic, full pressure. From $549.
Small filterswere the problem.
Ordinary shower filters exhaust in weeks because their media chambers are the size of a fist. Monolith XL carries a six-inch-deep chamber with four times the media, so contact time is real and the cartridge works for a full year.
4×
Filtration media
12 mo
Cartridge life
2.5 gpm
Rated flow, up to
Six stages, one cylinder.
316L Mesh Pre-Screen
A marine-grade sieve arrests sediment and scale before the media bed.
KDF-55 Alloy
Copper-zinc redox media neutralizes chlorine and dissolved heavy metals.
Catalytic Carbon
A deep carbon bed adsorbs chloramines, VOCs, and PFAS precursors.
FIR Ceramic
A ceramic polishing stage finishes the media bed for a noticeably softer feel.
Metered Vitamin-C
A capsule doses ascorbic acid to quench residual oxidants at the head.
The Oversized Chamber
Six inches of contact depth. The reason all of the above actually works.
Annual XL core cartridge: $149, or $129 with a subscription. Vitamin-C capsules from $15 per month.
Five finishes.One machine.
Every faceplate is machined from the same 316L billet, then PVD-hardened for life. Choose the one that disappears into your bathroom.
Why not the usual?
You have options. Here is the honest arithmetic, spec for spec.
| Monolith XLCuiven | Typical cartridge | Premium plastic | |
|---|---|---|---|
| Media volume | 4× oversized | Fist-sized | Standard |
| Stages | 6 named stages | 2–3 | 3–4 |
| Housing | 316L stainless / Ti | ABS plastic | Chrome-film plastic |
| Cartridge life | 12 months | 4–6 weeks | 2–3 months |
| Flow | 2.5 gpm, full pressure | Restricted | Reduced |
| Vitamin-C | Metered dosing | – | Optional |
| Housing warranty | Lifetime | 1 year | 1 year |
Body
- Outer diameter
- 7.5 in
- Chamber depth
- 6.0 in
- Housing
- 316L stainless / Ti
Flow
- Rated flow
- 2.0-2.5 gpm
- Face perforations
- 380-480
- Pressure drop
- < 2 psi
Service
- Cartridge life
- 12 months
- Swap time
- Under 5 min
- Housing warranty
- 15 yr / lifetime Ti
Questions,
answered.
No. Monolith XL is engineered for 2.0-2.5 gallons per minute with under 2 psi of pressure drop, full rainfall flow through a year of use.
Built to outlastthe bathroom.
Lifetime warranty on every housing we machine. And when you're ready, Opus brings the same standard to your glass.