Mansfield by Prier M-123-5035 300 Series 12" Stem Assembly

Copper stem with bright brass coarse threaded end with black rubber washer brass screw metal washer and grey graphite packings.

Complete 300 series faucet picture with grey handle polished chrome body copper tube and brass end.

WHAT OUR CUSTOMERS SAY…

“I was very happy with Noel’s Plumbing. I was searching for a fairly rare part and saw it listed on their website. After placing my order, I was informed that the item was actually on backorder. Noel’s Plumbing was upfront and honest right away, letting me know it might take some time to arrive. Throughout the wait, they consistently kept me updated, which I really appreciated. When the part finally came in, they shipped it out immediately. It arrived exactly as described and was precisely what I needed. Excellent communication, honesty, and follow-through. Thank you, Noel’s Plumbing! ”

-Dave F.

04/04/2026

$47.87

This item is a complete replacement stem assembly for the “original style” 300 series Mansfield wall hydrants (manufactured between 1970 and 2013), made by Prier Products.

We can ship anywhere the US Postal Service ships. For orders being shipped outside the US, please contact us at (888) ASK-NOEL, noelsplumbingsupply@fuse.net, or via the text widget on this screen.

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Mansfield Stem Assembly for 12″ Series 300 Hydrant

M-123-5035

The stem assembly has an overall length of 15 7/8 inches.
It is specifically designed for an 12-inch wall depth, measured from the back of the face plate to the water shut-off. It replaces the stem in a 378-08 or 379-08 hydrant.
The packaging includes the stem assembly, a metal O-ring, a support washer, and both left-hand (large flat) and right-hand (small thick) graphite packings to accommodate different faucet types.

Related Documents

300 Series Faucet Parts Breakdown

UPC: 670210370165

Customer submitted images.

Common questions about this product

Yes, this is the OEM recommended part.

If you’re not sure text us a picture 1-888-275-6635 or email us a picture at noelsplumbingsupply@fuse.net.

We will make sure you have the right part.

WHAT OUR CUSTOMERS SAY…

“Hello, I was in the shop on Tuesday and was greeted and helped by a gentleman named Jackson. He was extremely helpful, friendly and it was really a pleasure to see a young man working in this industry with knowledge and kindness. I run my my own small business and was a first time customer at Noel’s, being greeted and cared for in that manner will definitely bring about my return. I want to send me sincerest gratitude to your team. Thanks again! ”

-Jimmy M.

10/21/2022