JST GH vs ZH: Identify the Interface Before Ordering a Cable

JST GH and ZH are different wire-to-board connector systems. GH has 1.25 mm contact spacing and an external positive latch; ZH has 1.50 mm spacing and a different mating interface. A matching circuit count does not make them interchangeable.

Quick choice: for an existing board, identify its exact header and order the intended mating parts. For a new design, compare GH's latch and wire requirements with ZH's terminal choices and through-hole or SMT header options. Both catalogs list 1 A with AWG 26, so the larger pitch does not establish a higher current rating.

GH vs ZH comparison

These are original JST catalog references, not specifications for the alternative samples pictured below or a finished harness.

Item	JST GH	JST ZH
Pitch	1.25 mm	1.50 mm
Retention distinction	External positive latch holds the mating pair	Housing lance retains the terminal; this is not GH's external release latch
Catalog current	1 A AC/DC with AWG 26	1 A AC/DC with AWG 26
Catalog voltage	50 V AC/DC	50 V AC/DC
Catalog temperature	−40 to +105 °C	−25 to +85 °C
Contact and wire option	SSHL-002T-P0.2: AWG 30–26, insulation OD 0.76–1.00 mm	SZH-003T-P0.5: AWG 32–28, OD 0.50–0.90 mm; SZH-002T-P0.5: AWG 28–26, OD 0.80–1.10 mm
Four-position housing example	GHR-04V-S	ZHR-4
Board-side options	SMT top/side entry	Through-hole top/side entry and SMT options; match the exact version

Temperature limits include the temperature rise caused by current. Sources: JST GH catalog, pages 1–3; JST ZH catalog, pages 1–5, checked 29 September 2026.

Identify an unknown GH or ZH connector

Start with the PCB bill of materials or equipment drawing. Record the complete header reference, circuit count and orientation, then confirm the cable housing and terminal against its drawing. Names such as “small JST” or “1.5 mm cable” are insufficient purchasing specifications.

If the part number is unavailable, measure contact centers across several positions. A regular four-position row spans three pitches: 3.75 mm for GH or 4.50 mm for ZH. Divide the first-to-last center distance by the number of spaces, not the number of contacts. Body width and cavity opening width are different measurements.

Use that result to narrow the search, then inspect the mating shape and retention features. It does not establish brand origin. A visually similar replacement still needs an identified supplier drawing and a mating review.

Alternative ZH housings (top) and GH housings (bottom).

Explore GH-series alternative connectors and ZH-series alternative connectors. Confirm the selected alternative's own documentation before approving it.

Three choices that matter more than the series name

Match the wire to one specific terminal

ZH's overall wire range is covered by two terminal references. It is not one terminal accepting every combination of AWG 32–26 and 0.50–1.10 mm insulation diameter.

For example, an AWG 28 wire with 0.70 mm insulation OD fits the published dimensional range for SZH-003T-P0.5, but falls below the GH contact's listed OD range. AWG alone would miss that distinction. This is a dimensional screening example; the exact wire construction and crimp requirements still belong in the approval process.

Keep the specified wire in the RFQ. A purchasing substitution that changes insulation thickness can affect terminal fit even when the conductor gauge stays unchanged.

Compare the selected board connection

A through-hole board design makes ZH's relevant header options worth reviewing. An SMT design requires the exact footprint and entry direction for either series. Do not infer PCB interchangeability from a similar plastic outline.

Pitch describes the contact row, not the installed envelope. Include housing depth, insertion travel, cable bend space and nearby components. In an enclosure, the easiest connector to place on the PCB may be difficult to connect after the board is mounted.

Plan retention and service access

GH's external latch needs room for release. ZH's housing lance concerns terminal seating inside the housing; it should not be presented as the equivalent of that latch. Inspect terminal retention and completed connector mating separately.

Support the harness so routing forces do not continually load the interface. If shock or vibration matters, specify the actual test conditions and acceptance criteria. A visible latch or a larger housing does not qualify the finished assembly for that environment.

Angled view: alternative ZH housings (upper row) and GH housings (lower row).

Prepare a GH or ZH cable RFQ

Send a drawing that defines:

• The exact header, cable housing, terminal, circuit count and original-component or alternative-approval requirement.
• Pin-to-pin mapping with the viewing direction and pin-one reference, including empty positions.
• Wire gauge, insulation OD, wire material/specification and colors.
• Finished length, tolerance, measurement endpoints and requested end terminations or branches.
• Protection and labeling needs, sample/production quantities, operating conditions and required inspection criteria.

If the two ends intentionally use different series, specify each interface separately. A GH-to-ZH cable can bridge two correctly matched board connections; it does not let either housing plug into the other series' header.

Zeakka offers alternative connectors. For finished cable assemblies, original JST components can be sourced subject to exact part selection and availability, or unbranded alternatives can be reviewed. Original components are not sold separately. Specific ZH cable configurations and requested original-part availability are assessed per project.

See custom JST GH cable assemblies or send a GH/ZH RFQ. For broader identification, use the common JST connector types guide.

Frequently asked questions

Does ZH carry more current because its pitch is larger?

The referenced catalogs give both series 1 A with AWG 26. Assess the selected wire, loaded circuits, ambient temperature and complete assembly; pitch alone does not determine usable current.

Can GH terminals be installed in a ZH housing?

Do not substitute them. Specify the contact intended for the selected housing, with its approved wire and crimp requirements.

Is a ZR-marked header necessarily the wrong part for ZH?

No. The ZH catalog lists matching header references containing ZR. Check the complete reference and mating drawing rather than rejecting or accepting a part from a name fragment. That catalog relationship does not make GH and ZH interchangeable.