250 mL Flat-Bottom Bottle Insert for Z446-04500 (2/pk)

The Z446-500-A250F is the 250 mL flat-bottom bottle insert for the Hermle Z446-04500 4 × 500 mL angle rotor on the Z446 / Z446-K chassis — sold as a 2-pack. Each insert holds 1 × 250 mL flat-bottom bottle; the 4-position rotor takes 2 packs (4 inserts) for full symmetric loading, delivering 4 × 250 mL bottles per cycle (1 L total) at the host rotor's high-RCF range (10,367 × g). The F suffix denotes flat-bottom envelope (vs the conical envelope of the Z446-500-A250 sister insert) — same volume, different bottle geometry for workflows requiring flat-base bottle format.

Key Specifications

Compatibility & When to Order This SKU

Insert pairing — Z446-04500 500 mL angle rotor only. Order this SKU when:

1. Adding 250 mL flat-bottom bottle workflow to a Z446-04500 install — order 2 units for full 4-position symmetric loading (1 L total per cycle).
2. High-RCF cold-chain bulk-volume flat-bottom bottle prep — when the workflow specifies flat-base bottle geometry (over conical) for cell-pellet distribution, organic-extraction phase separation, or other protocol-specific reasons.
3. Mixed 500 / 250 mL workflow consolidation — when the chassis primarily runs 500 mL bottle workflows but occasional 250 mL flat-bottom processing arises.
4. Replacement inserts if a current set is damaged or worn.

Conical vs Flat-Bottom 250 mL — Why Two Insert SKUs

The Z446-500 250 mL insert pair serves the same volume but different bottle envelopes:

The flat-bottom bottle distributes pellet across a larger surface area (useful for organic-extraction phase separation, distributed cell-monolayer pellet workflows). The conical bottle (Hermle C1250) concentrates pellet at the tip (useful for efficient sample recovery from small cell pellets). Pick the A250F when flat-base geometry is the protocol-specified format.

Application Profile

Bulk-volume cell harvest in 250 mL flat-bottom — pelleting cells from 250 mL suspension culture batches at 4 × 250 mL parallel throughput; the flat-bottom bottle distributes the pellet across a wider base for protocols that resuspend the pellet in larger working volume.

Organic-extraction phase separation in 250 mL flat-bottom glass — when the workflow includes phase separation of aqueous and organic phases in 250 mL working volume and the flat-base geometry supports clean phase boundaries.

Cold-chain mid-volume protein-prep workflows in flat-bottom format — TCA, ammonium-sulfate, organic-precipitation in 250 mL working volume on the cold-chain refrigerated chassis with flat-base pellet distribution.

Vaccine-development intermediate prep at 250 mL flat-bottom — vaccine-development workflows that batch 250 mL flat-bottom bottles for intermediate concentration steps where the flat-base format is the protocol standard.

Environmental and analytical bulk sample prep at 250 mL flat-bottom — water, soil-extract, sediment-supernatant prep at 250 mL flat-bottom bottle scale.

Cross-format Z446-K core facilities — labs running both 250 mL flat-bottom (this SKU) and 250 mL conical (A250) workflows benefit from stocking both insert variants.

Ordering & Configuration

4-position symmetric loading. All 4 positions on the host rotor must use matching A250F inserts for symmetric balance at 8,000 rpm.

Bottle cap confirmation. All bottles must be securely capped before spinning at 8,000 rpm — at 250 mL working volume and high RCF, cap integrity is critical.

Bottle volume balance. When the 4 bottles carry different sample volumes, pre-balance pairs by total mass before spinning.

Z446-500-A250F ships as 2 inserts. Bottles (250 mL flat-bottom, 62 mm OD) are operator-supplied.

Confirm at quote: host rotor (Z446-04500 in inventory), chassis pairing (Z446 or Z446-K), bottle format (250 mL flat-bottom, 62 mm OD; for conical 250 mL use A250 insert with Hermle C1250 bottle), pack count (2 packs for full 4-position configuration), and lead time.

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

Z446-500 250 mL insert pair (Z446-04500 4 × 500 mL angle rotor):

- Z446-500-A250F (this product) — 250 mL flat-bottom (122 mm length)

- Z446-500-A250 — 250 mL conical (159 mm length, Hermle C1250 bottle)

Match the insert to the workflow's bottle envelope geometry — flat-base for distributed pellet workflows, conical for tip-concentrated pellet recovery.