1.8 mL Round Cryotube Adapter for Z216 5 mL Reaction Tube Rotor (6/pk)

The Z216-05-C18 is a 1.8 mL round-bottom cryotube adapter for the Hermle Z216 series 5 mL reaction tube rotor on the Z216-M / Z216-MK high-speed microcentrifuge chassis, sold as a 6-pack. The 5 mL reaction tube rotor accepts 5 mL conical tubes directly, but cryotubes have smaller envelopes and round-bottom skirted cryotubes (1.8 mL external-thread format) require a dedicated adapter to seat correctly and balance properly at high RCF. Sister adapter to the Z216-05-C10 (1.0 mL flat-cap format), both serve the same rotor but for different cryotube geometries.

Key Specifications

Compatibility & When to Order This SKU

Adapter pairing: Z216 5 mL reaction tube rotor only. The Z216-05-C18 is engineered to fit the 5 mL position envelope on the Z216 5 mL rotor. Order this SKU when:

1. Adding 1.8 mL round-bottom cryotube workflow to an existing Z216-M / Z216-MK + 5 mL rotor install.
2. Cryostorage aliquot prep for workflows that use 1.8 mL round-bottom skirted cryotubes (a common format in cell-line banking and protein-prep aliquoting).
3. Replacement adapters if a current set is damaged or worn.
4. Mixed-cryotube-format workflows. Pair with the Z216-05-C10 (1.0 mL flat-cap adapter) when the lab handles both flat-cap and round cryotube formats on the same chassis.

Cryotube Envelope Geometry

Round-bottom skirted cryotubes (typical 1.8 mL format from Nunc, Corning, Thermo, Greiner, Wuxi) have:

• A round (rather than flat) bottom that requires a matched concave adapter base to seat fully
• An external-thread skirt that protrudes beyond the cryotube barrel diameter. The C18 adapter's mouth accommodates this skirt
• A typical full length around 49–50 mm with cap

The C18 adapter is dimensioned for this envelope. Using a flat-cap adapter (C10) under a round-bottom skirted cryotube would leave the tube unsupported at the bottom and risk imbalance or tube damage at high RCF.

Application Profile

Cell-line cryopreservation banking. Cell-line freezing programs that use 1.8 mL round-bottom skirted cryotubes for the standard freeze format; the spin step concentrates cells before resuspension in cryoprotectant.

Master and working cell bank preparation. Research-grade cell banking workflows where each cell-line preparation generates batches of 1.8 mL cryotube aliquots for cryostorage.

Biobank patient-sample aliquots. Clinical-research biobanks using 1.8 mL skirted cryotubes for patient-sample aliquots prepared for cryostorage and longitudinal analytical reference.

Protein and reagent aliquoting for freeze storage. Antibody, enzyme, and reagent aliquot prep into 1.8 mL cryotubes for −80 °C storage.

Cross-format Z216 microcentrifuge consolidation: labs running both 5 mL conical workflows and 1.8 mL round cryotube workflows can use the same chassis + rotor with the C18 adapter swapped in for cryotube runs.

Loading & Balance

Symmetric adapter loading. Pair adapter positions across the rotor by tube mass; all positions in a balanced pair must use matching adapter + tube format.

Cryotube cap confirmation. Skirted cryotube external-thread caps must be fully torqued before spinning, partial cap seating risks sample loss at high RCF and rotor / adapter contamination.

Adapter seat verification. Confirm each C18 adapter is fully seated in its 5 mL position envelope before loading the cryotube.

Ordering & Configuration

Z216-05-C18 ships as 6 adapters. Cryotubes are operator-supplied (commodity biobank cryotube formats from major commercial suppliers).

Confirm at quote: rotor pairing (Z216 5 mL reaction tube rotor in inventory), chassis pairing (Z216-M or Z216-MK), cryotube format (1.8 mL round-bottom skirted confirmed), pack count needed, and lead time.

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

Z216 5 mL rotor cryotube adapter family:

- Z216-05-C18 (this product): 1.8 mL round-bottom cryotube adapter

- Z216-05-C10: 1.0 mL flat-cap cryotube adapter

Match the adapter to the cryotube format. Workflows using both cryotube formats benefit from stocking both adapter SKUs.