Used RGA Mass Spectrometer Head

How Much Does a Used RGA Mass Spectrometer Head Cost in 2026?

Used RGA heads trade at $1,000–$6,000 in 2026 depending on OEM, mass range, and interface. SRS RGA 200 (1–200 amu, USB) runs $1,000–$1,800 as-removed; SRS RGA 300 (1–300 amu) trades at $1,500–$2,800. MKS QuadMass 422 and INFICON Transpector heads trade at $2,500–$4,500. Pfeiffer PrismaFlex and OMA units run $3,000–$6,000 due to their integration with Pfeiffer vacuum systems.

New OEM pricing: SRS RGA 200 lists at $3,200–$4,500; Pfeiffer PrismaFlex at $8,000–$14,000. Used units save 40–60% with 2–4 week lead time vs. 8–16 weeks for new. Units with filament hours exceeding 8,000 hours or last calibration older than 18 months should be discounted by 25–35% to account for required maintenance before deployment.

RGA Mass Spectrometer Head Specifications and Compatible Tools

| Parameter | SRS RGA 200 | MKS QuadMass 422 | Pfeiffer PrismaFlex | |-----------|-------------|------------------|---------------------| | Mass range | 1–200 amu | 1–200 amu | 1–100 amu (standard) | | Operating pressure | 10⁻⁴–10⁻⁸ Torr | 10⁻⁴–10⁻⁸ Torr | 10⁻³–10⁻⁹ Torr | | Sensitivity | 5×10⁻¹⁴ A/Torr | 1×10⁻¹³ A/Torr | 1×10⁻¹² A/Torr | | Interface | USB / RS-232 | Analog / Ethernet | Ethernet / RS-485 | | Filament type | Y₂O₃ coated W | Rhenium | Iridium coated W | | Flange | CF 2.75" | CF 2.75" | DN40 CF |

Compatible systems: Applied Materials Centura process chambers, Lam Research etch systems, Novellus CVD chambers, and any vacuum system operating in the 10⁻⁴ to 10⁻⁸ Torr range. Compatibility warning: Pfeiffer PrismaFlex heads use proprietary RS-485 protocol and are NOT compatible with SRS or MKS control software without a protocol converter — confirm software compatibility before purchase.

What to Check Before Buying a Used RGA Head in 2026

1. Filament condition and hours: Request filament runtime log. Y₂O₃-coated tungsten filaments last 6,000–12,000 hours; rhenium filaments 3,000–6,000 hours. At >80% of rated life, factor in filament replacement ($150–$400) plus 4–8 hours downtime for installation and bakeout.
2. Mass calibration verification: Run a calibration check on known gas peaks (N₂ at 28, Ar at 40, H₂O at 18). Peak centers drifting >0.1 amu from nominal indicate quadrupole mass filter wear — not field-repairable on most models.
3. Vacuum flange condition: Inspect the CF flange knife-edge for nicks >0.05mm depth. A damaged knife-edge causes virtual leaks that look like process gas contamination — a common misdiagnosis with used RGA heads.
4. Sensitivity baseline: Test minimum detectable partial pressure. Units from 2003–2012 production should read <1×10⁻¹² Torr at 10⁻⁸ system base pressure. Degraded electron multipliers reduce sensitivity by 10x per decade of age — confirm against spec.
5. Electronics and firmware: Check analog output accuracy with a known reference gas at 1×10⁻⁶ Torr. Output drift >10% of reading indicates A/D converter aging in older units. Firmware updates (free from SRS/Pfeiffer) resolve most software-side calibration issues in units post-2010.

Frequently Asked Questions

SRS RGA 200 vs. Pfeiffer PrismaFlex — which is better for process monitoring? SRS RGA 200 is the workhorse of the industry — simpler firmware, lower cost, faster scan rates (up to 50 amu/sec). PrismaFlex wins for sensitivity-critical applications (<10⁻¹⁰ Torr partial pressure detection) and integrates natively into Pfeiffer vacuum systems. For a standalone semiconductor etch tool, SRS RGA 200 is the better value; for a research system needing the lowest detection limits, go PrismaFlex.

How reliable are used RGA heads compared to new? Properly tested used RGA heads deliver equivalent results to new for 3–6 years from purchase, provided the filament and electron multiplier are within spec. The key failure modes (filament wear, multiplier aging) are detectable with a 30-minute bench test — don't skip it.

How often do RGA heads need recalibration? Every 12 months in production, or after any vacuum system event (pump failure, atmospheric exposure, major process change). Recalibration at a certified vacuum instrument shop runs $300–$600 — budget this annually into total cost of ownership.

Can a used RGA head be upgraded with a modern interface? SRS RGA 100/200 heads can be updated with a USB control board ($400–$700) to replace legacy RS-232. MKS QuadMass units can accept an Ethernet upgrade card. Pfeiffer units are harder to retrofit — proprietary architecture limits third-party upgrades.

Last updated: May 2026. Pricing reflects current 2026 secondary market conditions. Request a quote for current availability.