7 × 50 mL Round-Bottom Insert for Z306-100 (2/pk)

The Z306-100-A50R is the 7-position 50 mL round-bottom tube insert for the Hermle Z306-100 swing-out bucket on the Z307 chassis 4-place rotor — sold as a 2-pack. Each insert holds 7 × 50 mL round-bottom tubes; the 4-bucket rotor configuration takes 2 packs (4 inserts) for full symmetric loading, delivering 28 × 50 mL round-bottom tubes per cycle (1.4 L total volume per cycle) when fully equipped. Sister insert to the A50 (50 mL conical format) — both serve the same 50 mL workflow envelope but for different tube geometries.

Key Specifications

Compatibility & When to Order This SKU

Insert pairing — Z306-100 swing-out bucket only. Order this SKU when:

1. Adding 50 mL round-bottom tube workflow to an existing Z307 + Z306-100 install — order 2 units for full 4-bucket symmetric loading (28 tubes/cycle, 1.4 L total).
2. Glass round-bottom tube workflows when the protocol requires glass for chemical compatibility (organic solvents, autoclave reuse) and the round-bottom geometry is specified.
3. Replacement inserts if a current set is damaged or worn.

Application Profile

Round-bottom vs conical (vs the A50 sister). The A50R holds 50 mL round-bottom tubes (typical clinical / serological round-bottom glass or polypropylene formats, 90–108 mm length). The A50 sister insert holds 50 mL conical tubes (Falcon, Corning, 75–100 mm length). The two formats have different shoulder geometries; using the wrong insert risks tube fit problems and balance issues.

Glass tube workflow compatibility. 50 mL round-bottom glass tubes support workflows requiring glass for organic-solvent compatibility, repeated autoclave reuse, or precise volume measurement (graduated glass tubes).

4-bucket symmetric loading. All 4 buckets must use matching A50R inserts for symmetric balance.

Design Architecture

Glass-compatible 50 mL workflows — organic-extraction, chemical-prep, and precipitation workflows in 50 mL working volume that require glass tube compatibility.

Clinical and clinical-research serological workflows — 50 mL round-bottom tubes used in some serological prep protocols.

Cell-culture pellet recovery in 50 mL round-bottom — when the protocol uses round-bottom glass over conical for specific resuspension or solvent-compatibility requirements.

Bench-scale protein prep in glass round-bottom — TCA, ammonium-sulfate, organic-precipitation steps where glass tube reuse and chemical compatibility justify the round-bottom format choice over disposable conical polypropylene.

Educational and graduate-level chemistry / biochemistry teaching — workflows specifying round-bottom glass for protocol-fidelity teaching exercises.

Cross-format Z307 chassis consolidation — labs that run both round-bottom and conical 50 mL workflows benefit from stocking both A50 and A50R inserts on the same bucket and chassis.

Ordering & Configuration

4-bucket symmetric loading. All 4 buckets must use matching A50R inserts. Mixed-bucket configurations produce mass asymmetry.

Per-insert symmetric loading. Within each insert, the 7 round-bottom tubes should be balanced symmetrically — pair tubes by mass.

Tube cap confirmation. All round-bottom tubes must be capped before spinning at 4,500 rpm.

Z306-100-A50R ships as 2 inserts. 50 mL round-bottom tubes (glass or polypropylene) are operator-supplied.

Confirm at quote: bucket pairing (Z306-100 in inventory), chassis pairing (Z307), tube format (50 mL round-bottom; A50 for conical), pack count (2 packs for full 4-bucket configuration), and lead time.

Warranty: 5-Year Hermle warranty (3 years full + 2 years drivetrain) on the inserts.

Z306-100 bucket 50 mL insert pair:

- Z306-100-A50R (this product) — 7 × 50 mL round-bottom

- Z306-100-A50 — 7 × 50 mL conical

Match the insert to the workflow's tube geometry. Both deliver 28-tube parallel throughput on the full 4-bucket configuration; only the tube geometry differs.