Seiko ColorPainter H-Series Printhead GP U00129498600

The Seiko ColorPainter H-Series Inkjet Head GP (part number U00129498600, also cross-referenced as U00112458300) is the genuine original replacement printhead for the OKI ColorPainter H-74s, H-104s, H2-74s, and H2-104s large-format eco-solvent and mild-solvent production printers. Built on Seiko's I-Series industrial piezo inkjet platform, this 508-nozzle head delivers 18 kHz firing frequency with a multi-drop volume system based on multiples of 12 pl (up to 7 drops, approximately 84 pl maximum) — the same printhead architecture used across the H-series 8-head array that gives the ColorPainter H platform its production-class throughput of up to 55 m²/h in 8-colour mode and 100 m²/h in 4-colour mode. Every U00129498600 we stock at Digiprint USA is 100% genuine original Seiko — not aftermarket, not compatible, not refurbished.

Part number cross-reference advisory. This head is listed under two Seiko part numbers — U00129498600 and U00112458300 — across different supplier catalogues, with the direction of supersession described inconsistently in the market. Both numbers refer to the same Seiko I-Series H-series GP printhead assembly. If your service documentation shows either number, contact us before ordering so we can confirm the current active stock number and ensure you receive the correct assembly.

Replace head cables at the same time. It is strongly recommended to replace the head data cables when installing a new printhead in the ColorPainter H-series. Worn cables are a leading cause of nozzle communication errors and drop-out after installation. Order replacement cables before scheduling the swap.

Technical Specifications

Compatible Printers

• OKI ColorPainter H-74s (74" / 188 cm)

• OKI ColorPainter H-104s (104" / 264 cm)

• OKI ColorPainter H2-74s (74" / 188 cm)

• OKI ColorPainter H2-104s (104" / 264 cm)

Not sure this is the correct head for your specific ColorPainter H-series model? Contact us before ordering to confirm the correct part number and assembly type.

What Does "GP" Mean?

GP stands for Guard Plate — a Seiko designation indicating that this printhead ships as a complete assembly including the guard plate component. The guard plate is a precision-machined protective plate mounted at the nozzle face of the printhead that shields the nozzle array from media contact and mechanical damage during printing. On the ColorPainter H-series, the GP assembly is the standard serviceable replacement unit — the guard plate is integral to the assembly and is replaced simultaneously with the head. This is distinct from bare head replacements (without guard plate) that exist for some other Seiko platforms. When replacing a head in the ColorPainter H-series, the GP assembly is the correct part.

The ColorPainter H-Series 8-Head Architecture

Unlike the ColorPainter M-64s (which uses a multi-channel head where one head serves two ink channels), the ColorPainter H-74s and H-104s use an array of eight individual printheads — one head per ink colour in 8-colour mode. The H-series ink configuration is: Cyan, Magenta, Yellow, Black, Light Cyan, Light Magenta, Grey, and Light Grey. Each head in the 8-head array is an identical U00129498600 assembly. This architecture allows two operating configurations:

• 8-colour mode — one head per colour for maximum image quality (up to 55 m²/h)

• 4-colour mode — two heads per colour (CMYK doubling) for maximum production speed (up to 100 m²/h)

Because all eight heads in the H-series array are identical, a single U00129498600 stock unit is the correct replacement regardless of which colour position in the carriage requires service. This simplifies inventory management — one part number covers every head position in the printer.

Smart Nozzle Mapping — Production Uptime Feature

The Seiko I-Series heads in the ColorPainter H platform include Smart Nozzle Mapping — a firmware-level nozzle compensation system that reassigns firing data from clogged or non-performing nozzles to adjacent functional nozzles without any loss in print quality. Each head can transparently compensate for up to 10 clogged nozzles, which means partial nozzle blockage does not immediately force a head replacement or cause visible banding in production output. This feature is particularly valuable in high-throughput production environments where unplanned downtime for head maintenance is costly. When head replacement is eventually required, the U00129498600 is the direct like-for-like replacement — no recalibration of the Smart Nozzle Mapping table is required as the system automatically recalibrates to the new head's nozzle performance profile.

H-Series vs H2-Series — Ink System Difference

The U00129498600 printhead is compatible with both the original H-series (H-74s, H-104s) and the H2-series (H2-74s, H2-104s) printers, but the two generations use different ink formulations. The original H-series uses a mild solvent / low-solvent ink set designed for excellent colour and outdoor adhesion on standard vinyl and banner substrates. The H2-series uses Seiko's VX or GX high-viscosity ink formulations, which deliver wider colour gamut, higher outdoor durability, and superior adhesion on a broader substrate range. When replacing the head, confirm you are using inks appropriate for your specific H or H2 series printer — installing the correct printhead is only part of a successful service; the correct ink system must also be maintained.

Applications

• High-volume outdoor signage — banners, billboard prints, building wraps, and outdoor display graphics at production speeds up to 100 m²/h

• 8-colour wide-gamut graphics — photography, fine gradients, and colour-critical display graphics with Light Cyan, Light Magenta, Grey, and Light Grey channels

• Vehicle and fleet graphics — high-coverage vinyl wrap and fleet livery production requiring reliable high-speed output

• Retail and POS production — high-volume point-of-sale and retail display production on a wide range of coated and uncoated solvent media

Warranty Notice

This printhead carries a manufacturer warranty. Warranty coverage is voided by: use of non-original or incompatible inks, clogged or damaged nozzles caused by incompatible inks or improper maintenance, misuse, neglect, failure to perform periodic maintenance, improper media loading, and damage from third-party ink systems or bulk inks. Due to the sensitive nature of inkjet printhead components, Digiprint USA cannot accept returns or refunds once the printhead has been installed. All sales are final. Contact us to confirm the correct part number for your specific H-series model before ordering.

Why Buy from Digiprint USA

• 100% genuine original Seiko / OKI ColorPainter H-series printhead — not aftermarket, not refurbished

• In stock in Doral, Miami FL — same day shipping before 2PM EST

• One part number covers all 8 head positions in the H-74s and H-104s carriage array

• Covers H-series (mild solvent) and H2-series (VX/GX ink) platforms from a single stocked part

• Free technical support — we confirm U00129498600 vs U00112458300 cross-reference, GP assembly type, and H vs H2 ink compatibility before you order

View our full range of genuine Seiko and OKI ColorPainter printheads stocked by Digiprint USA.

Frequently Asked Questions

What does "GP" mean in the printhead name?
GP stands for Guard Plate — it indicates this is a complete printhead assembly that includes the guard plate component. The guard plate is a protective precision shield mounted at the nozzle face, and on the ColorPainter H-series it is integral to the serviceable replacement assembly. When replacing a head in the H-74s or H-104s, the GP assembly is the correct part — no separate guard plate needs to be sourced or transferred from the old head.

Are all 8 heads in the ColorPainter H-74s / H-104s the same part?
Yes. The ColorPainter H-series 8-head array uses identical U00129498600 assemblies in every position. Regardless of which colour channel position requires replacement — whether Cyan, Magenta, Yellow, Black, Light Cyan, Light Magenta, Grey, or Light Grey — the physical head part is the same. This makes inventory management straightforward: one stock unit covers every head position.

What is the relationship between U00129498600 and U00112458300?
Both numbers refer to the same Seiko I-Series H-series GP printhead assembly. Different supplier catalogues describe the supersession direction inconsistently — some list U00129498600 as the newer part replacing U00112458300, while others reverse this. Rather than risk supplying the wrong revision, we recommend contacting us before ordering so we can confirm the currently active stock number and ensure you receive the correct assembly for your printer.

Can the ColorPainter H-series head be used in the H2-series printers?
Yes — the U00129498600 printhead assembly is physically compatible with both the H-series (H-74s, H-104s) and H2-series (H2-74s, H2-104s) printers. However, the two generations use different ink systems: the original H-series uses mild solvent inks, while the H2-series uses Seiko's VX or GX high-viscosity ink formulations. Ensure your printer's ink system is correct for the generation before replacing the head.

Do you ship the OKI ColorPainter H-series printhead to Latin America?
Yes — same day shipping from our Doral, Miami FL warehouse. Our location is ideal for Latin American large-format production operations, OKI ColorPainter service centres, and commercial signage producers using freight forwarders in the Doral area.