Delta RP50587 cartridge
DIAMOND Seal (DST) ceramic valve, one-handle faucets.
Checked against the manufacturer
- Fits
- DIAMOND Seal (DST) ceramic valve, one-handle faucets
- Used in
- Kitchen sink, Bathroom sink
- Handles
- Single
- How it works
- Single handle; top switch on some handles is a limit stop.
- Volume control
- Yes
- Height
- 2-1/2 in.
How to recognize it
- Ceramic valve cartridge with orange O-ring gasket
- Body about 1-27/64 in. across; guide pins on the bottom (secondary)
Don't mix it up
- Narrower DST cartridges (about 1-17/64 in.) are different parts (secondary).
- RP3614A repair kit does not fit it.
- Ferguson (a major plumbing distributor) lists it for DIAMOND Seal kitchen AND bathroom models that use the 36 mm cartridge; Delta's own page only confirms kitchen models. Retail listings name 500-DST, 501-DST, 520-DST, 501LF-HDF and 520LF-HDF (unconfirmed by Delta).
Good to know
Confirmed for Victorian 955-DST pull-down kitchen and 9178 kitchen faucets (Delta Q&A). Not serviceable: no repair parts, orange gasket not sold separately. Remove bonnet nut with an adjustable wrench; handle with a 1/8-inch Allen key. Out of stock on deltafaucet.com when checked 2026-10-29 (not marked discontinued).
Before you buy: pull the old part and compare it side by side. Similar-looking parts often don't swap.
Where to buy
Search Amazon · Search Home Depot · Search eBay
We may earn a commission when you buy through these links, at no extra cost to you. Details.