Dresser Gasket — Style 88 | Replacement Gasket for Style 88 Brass Compression Fittings

Copper Tubing | Brass Compression Fittings | Grade 27 BUNA-S | No Soldering Required | CTS Dimensions

Overview

The Dresser Style 88 Gasket is the factory-specified replacement sealing element for Dresser Style 88 Brass Compression Fittings — the small-diameter bottle-less connectors designed exclusively for use with copper tubing (CTS — Copper Tube Size dimensions). The Style 88 fitting and its gasket are dimensionally distinct from all other Dresser compression fitting styles because copper tubing ODs follow CTS standards, which differ from nominal iron pipe size (IPS) ODs of the same nominal designation. The Style 88 gasket is machined and molded to match CTS tubing ODs — it is not interchangeable with Style 65 or Style 90 gaskets.

Style 88 fittings are the field-preferred connection method for copper tubing in gas service line work, where flame-free installation eliminates the hot work permit requirement, and in water service and mechanical piping where soldering is impractical or undesirable. The Style 88 system employs Dresser's compression sealing principle — the gasket is compressed against the CTS tubing OD by the end nut, producing a leak-proof flexible joint with no threading, soldering, flaring, or special tools required.

What Is the Dresser Style 88 Brass Compression Fitting?

The Dresser Style 88 is a bottle-less compression fitting in a brass body, designed for plain-end copper tubing in sizes typically up to 1 in CTS. The brass body provides corrosion resistance in wet service and avoids galvanic incompatibility with copper tubing. Style 88 fittings can also be used in tandem with Style 65 iron pipe fittings via an insulating adapter — the insulating adapter fits over the copper tubing and into a Style 65 coupling body, creating a galvanically isolated transition from copper to steel pipe. This is common in gas service line applications where the underground copper service line transitions to above-ground steel at the meter set.

Key Features

• CTS-Dimensioned Gasket — Purpose-Built for Copper Tubing: Molded to match CTS (Copper Tube Size) ODs — not nominal IPS pipe ODs. Copper tubing ODs are larger than same-nominal IPS pipe ODs; do not substitute Style 65 or Style 90 gaskets.
• Brass Body Fitting Compatibility: Designed for use with Dresser's brass fitting body — prevents galvanic corrosion at the copper-to-fitting interface common when iron or steel fitting bodies contact copper tubing in wet service.
• No Soldering, Flaring, or Hot Work Required: Eliminates flame and heat entirely — critical in gas service line work where hot work permits are avoided, and in retrofit work where open flame is impractical near existing utilities.
• Ships Assembled and Ready to Install: Style 88 fittings ship assembled. Loosen end nuts, stab copper tubing into both ends, tighten to specified torque.
• Compatible with Style 65 System via Insulating Adapter: Insulating adapters allow Style 88 and Style 65 to be used in tandem at copper-to-steel pipe transitions — the adapter fits over the copper tubing OD and converts it to a fitting that inserts into the Style 65 body ID.
• Grade 27 BUNA-S Standard: Wide compatibility with water, gas, air, and general utility service fluids to 212°F. Grade 42 BUNA-N available for oil and hydrocarbon service.

Gasket Specifications

? CTS vs. IPS DIMENSIONS: Copper tubing (CTS) ODs are larger than same-nominal iron pipe size (IPS) ODs. A 1/2 in copper tube has a 0.625 in OD; a 1/2 in IPS pipe has a 0.840 in OD. Always confirm whether your application requires CTS (Style 88) or IPS (Style 65 or Style 90) gaskets. Installing an IPS gasket on copper tubing or vice versa will result in an improper seal.

Questions? Contact us at sales@watermainsupply.com or call 281.664.8000.