The IPS2050-P-S4 is the 4-arm stainless steel propeller in the IPS2050 overhead stirrer accessory line — sold separately at $110 for use on the OS-20L (IPS2050-20 / -20-E) and OS-40L (IPS2050-40 / -40-E) overhead stirrer chassis. This is the default propeller that ships with the IPS2050-20 / -40 chassis — it is sold separately as a replacement / spare for institutional inventory or for multi-vessel facility procurement where labs running multiple chassis simultaneously want a dedicated 4-arm propeller per vessel without relying on cross-chassis swap.
Key Specifications
| SKU | IPS2050-P-S4 |
| Type | 4-Arm Propeller, stainless steel |
| Flow pattern | High-coverage axial-radial — the general-purpose workhorse geometry |
| Material | Stainless steel (general-purpose chemistry compatibility — aqueous, mild solvents, neutral-pH formulations, food-grade workflows) |
| Compatible chassis | IPS2050-20 / -20-E (OS-20L) and IPS2050-40 / -40-E (OS-40L) overhead stirrers |
| Default-included status | Ships included with IPS2050-20 / -40 / -20-E / -40-E chassis — sold separately as replacement / spare |
| Mounting | Feed-through chuck on chassis — tool-less tightening / loosening |
| Family sister SKUs | IPS2050-P-S1 (one-line), IPS2050-P-S2 (centrifugal), IPS2050-P-S3 (paddle w/flat holes) |
| Teflon equivalent | IPS2050-P-T4 (4-arm PTFE — aggressive-solvent compatibility, $172) |
| List price | $110 |
Why a 4-Arm Propeller — General-Purpose Workhorse
The 4-arm geometry produces high-coverage axial-radial flow — fluid is driven both vertically through the vessel and horizontally outward, generating the broadest mixing pattern of the four IPS2050 stainless impeller geometries. This is why Benchmark Industrial specifies it as the default included propeller: it covers the largest range of typical workflows without operator pre-selection.
Pick the 4-arm propeller (IPS2050-P-S4) when:
- General-purpose mixing is the workflow (not particulate-suspension-specific or dissolution-specific or high-viscosity-specific)
- Replacement / spare for the included propeller (worn, lost, damaged)
- Multi-vessel facility procurement — one 4-arm propeller per chassis at low marginal cost
- Aqueous and mild-solvent chemistry (stainless compatible)
Pick the Teflon equivalent (IPS2050-P-T4) when sample chemistry includes aggressive solvents, high-acid, or high-base formulations.
Procurement-Path Decision: Spare vs Workflow-Specific
| Path | Why | Best fit |
| Replacement / spare | Default propeller wears, gets damaged, or gets lost in shared-lab environments | Multi-investigator facility, training labs, frequent-protocol-swap workflows |
| Multi-vessel inventory | Each chassis gets its own dedicated propeller (no cross-chassis swap delays) | Multi-chassis facility procurement, parallel-run mixing protocols |
| Workflow-specific (-S1 / -S2 / -S3) | Specific flow-pattern requirement (axial-only, radial-only, mixed-turbulent) | Protocol-development, viscosity-tuned workflows |
Stainless Family Flow-Pattern Comparison
| SKU | Geometry | Flow pattern | Best for |
| IPS2050-P-S1 | One-line | Axial | Particulate suspension |
| IPS2050-P-S2 | Centrifugal | Radial | Dissolution / solution prep |
| IPS2050-P-S3 | Paddle w/flat holes | Mixed turbulent | Higher-viscosity work |
| IPS2050-P-S4 (this product) | 4-arm | High-coverage axial-radial | General-purpose workhorse (default included) |
Application Profile
General-purpose lab mixing at the 5–40 L vessel scale — the workflow the IPS2050 chassis was designed around.
Replacement / spare procurement for institutional inventory where the included propeller has worn, been damaged, or gone missing in shared-lab environments.
Multi-vessel facility procurement — labs running multiple chassis simultaneously inventory one dedicated propeller per chassis to avoid cross-chassis swap delays during parallel runs.
Educational laboratory teaching — graduate / undergraduate programs introducing overhead-stirrer mixing concepts benefit from the workhorse 4-arm geometry as the baseline reference impeller.
Pharmaceutical / cosmetic / food-science general formulation at low-to-medium viscosity where the broad-coverage flow pattern is sufficient.
Ordering & Configuration
Pair with chassis. Confirm OS-20L (IPS2050-20 / -20-E) or OS-40L (IPS2050-40 / -40-E) chassis inventory at order — the propeller is workflow-incomplete without a chassis.
Confirm at quote: chassis pairing, replacement-vs-multi-vessel procurement intent, sample-chemistry compatibility (stainless vs PTFE / Teflon decision), and lead time.
Warranty: Per Benchmark Industrial standard accessory terms — confirm at quote.
IPS2050 stainless propeller selection:
- IPS2050-P-S1 — One-line, axial — particulate suspension
- IPS2050-P-S2 — Centrifugal, radial — dissolution / solution prep
- IPS2050-P-S3 — Paddle w/flat holes, mixed turbulent — higher-viscosity
- IPS2050-P-S4 (this product) — 4-arm, general-purpose (default included with chassis)
Pick the 4-arm propeller for general-purpose mixing or as replacement / spare; sister geometries cover specific flow-pattern requirements; PTFE / Teflon equivalents (IPS2050-P-T1 through -T4) cover aggressive-chemistry compatibility.
