
Alternatives to the discontinued Sure-Fit™ fittings
The legacy Sure-Fit™ connectors have been obsoleted since quite some time, but there are certainly modern fitting alternatives that can accomplish similarly or better tubing connections. As outlined below, Biotech Fluidics generally recommends the MarvelXACT™ series of fittings as replacement for the discontinued Sure-Fit™ connectors within HPLC and UHPLC instruments.


When originally launched by Isolation Technologies, the Sure-Fit™ connector was an innovative solution to the problem that different HPLC systems and columns could have different internal 10-32 port depths depending on the manufacturer. The port depth variability created issues with leaking connections and dead volumes which the Sure-Fit™ connectors solved with their unique internal spring-tensioned mechanism that automatically self-adjusted to virtually any port depth while maintaining constant pressure on the 1/16” OD tubing. However, after IDEX Health & Science acquired Isolation Technologies in 2008, the product program was revised and the Sure-Fit™ connectors were finally discontinued in 2016, in favour of the more modern MarvelX™ and later MarvelXACT™ fitting systems.
The MarvelXACT™ fitting system ensures leak free connections without any dead volume in any 10-32 port by using a ferrule-free design. Its torque-limiting fitting eliminates the risk of overtightening, thus warranting perfectly sealed connections up to 1300 bar (19000 psi). With its pre-fitted 1/32” OD stainless steel tubing (with rigid 1/16” ends) with internal diameters from 100 µm up to 254 µm and lengths from 100 to 600 mm, these forms the perfect (U)HPLC system flow paths. In addition, tubing assemblies with PEEK-lined stainless-steel or PEEKsil™ materials with internal dimensions from 25 µm are available as alternatives.
To learn more about the MarvelXACT™ tubing assemblies and their torque-limiting fitting system follow the link to the product pages, or contact Biotech Fluidics for additional guidance regarding fittings within your (U)HPLC instrument.
Discontinued Sure-Fit™ products
Part No. | Description | Port | Pressure Rating | Head Style | Material |
---|---|---|---|---|---|
9500-01005-010 | Sure-Fit™ Single End Fitting, 1/16” x 0.005” x 10 cm | 10-32 Coned | 6,000 psi (414 bar) | Diamond Knurl | SST |
9500-01007-010 | Sure-Fit™ Single End Fitting, 1/16” x 0.007” x 10 cm | 10-32 Coned | 6,000 psi (414 bar) | Diamond Knurl | SST |
9500-01010-010 | Sure-Fit™ Single End Fitting, 1/16” x 0.010” x 10 cm | 10-32 Coned | 6,000 psi (414 bar) | Diamond Knurl | SST |
9500-01020-030 | Sure-Fit™ Single End Fitting, 1/16” x 0.020” x 30 cm | 10-32 Coned | 6,000 psi (414 bar) | Diamond Knurl | SST |
9502-01007-HP | Sure-Fit™ Single End Fitting, 1/16” x 0.007”, U-Shape for Agilent 1100 System | 10-32 Coned | 6,000 psi (414 bar) | Diamond Knurl | SST |
9504-01005-050 | Sure-Fit™ Single End Fitting, 1/16” x 0.005” x 50 cm | 10-32 Coned | 6,000 psi (414 bar) | Diamond Knurl | PEEK, Natural |
9504-01007-050 | Sure-Fit™ Single End Fitting, 1/16” x 0.007” x 50 cm | 10-32 Coned | 6,000 psi (414 bar) | Diamond Knurl | PEEK, Natural |
9504-01010-050 | Sure-Fit™ Single End Fitting, 1/16” x 0.010” x 50 cm | 10-32 Coned | 6,000 psi (414 bar) | Diamond Knurl | PEEK, Natural |
9500-FP | Sure-Fit™ Replacement Ferrule | 10-32 Coned | 6,000 psi (414 bar) | - | PEEK, Natural |