HP 738M 300-ml Magenta DesignJet Ink Cartridge (676N0A)

What this part is

676N0A is HP’s 300-ml Magenta for the 738M run, supplied with the magenta printhead inside the tank rather than as a separate component. One cartridge per box.

Which printers take this part

HP part number 676N0A — genuine HP 738M 300-ml Magenta, one cartridge. The machines HP names for it are the T870 and XT870 plus the XT950 and XT950 MFP. Anything in the T850 family falls outside that list and needs the plain 738 magenta instead. If the only identifier you have is the package name your school bought, we can map it for you over the phone before a requisition goes in, or you can work it out from the poster printer ink cross-reference.

What the magenta channel does on this platform

The 738M range is black, cyan, magenta and yellow, so magenta carries every red, purple and warm mixed tone on its own — there is no second ink to share that load in this range. The integrated printhead shortens the troubleshooting path: if magenta prints thin or drops out in stripes, the replacement you order is this cartridge, and fitting it refreshes the nozzles for that color at the same time.

Tank size and how fast magenta drains

Magenta empties on photographic work — skin tones, sunset and autumn backgrounds, anything with a warm mid-tone — rather than on the text and dark fills that pull the black channel down. A school printing student portraits and photo collages will get through magenta faster than a school printing mostly typographic displays, and that is the number to weigh the tank size against. Every milliliter in this 300-ml cartridge costs about 17% less than the same magenta in the 130-ml A24VNA; turned the other way round, the small tank carries a 20% premium per milliliter. If magenta is one of your heavy channels, the larger tank is the cheaper ink.

Do not order this one by mistake

The part that gets confused with this one is 676M7A, the 738 Magenta. Same color, same 300-ml size, same price, and one character different in the number — but HP lists 676M7A for the T850 family and this cartridge for the XT950 family. They overlap only on the T870 and XT870. If your machine is an XT950 or XT950 MFP, 676N0A is the part; if it is a T850 or T850 MFP, it is not.

Specifications

Questions schools ask about this cartridge

Our tank is labelled 676M7A. Is that this cartridge?

Not quite. 676M7A is 300-ml magenta in the plain 738 range for the T850 and T870 families. 676N0A is the 738M version for the T870 and XT950 families. The price is the same either way, so the only thing that matters is the machine.

Does the magenta come with a printhead?

HP’s own description of the 738M says the printhead is integrated into the cartridge, so fitting 676N0A also puts a fresh nozzle array on the magenta channel. There are no separate tools or alignment steps beyond what the printer’s on-screen guide walks you through.

Can we mix a 300-ml magenta with 130-ml colors?

HP’s listing does not state a restriction either way, so ask us to check the mix against your model before you order. Schools often want to run the heavy channels large and the light ones small, and we would rather confirm it than have you guess.

How do we get a quote on school letterhead?

Call 866-788-7900 or email sales and we will send a quote you can attach to a PO. Supply orders ship at no charge.

Ordering

Free shipping and school POs on every ink order. Genuine HP part. Not sure which part fits your machine? Call 866-788-7900 or see all genuine HP parts by number.