Part family guide

Delta DST Diamond Seal Cartridge Family

Diamond Seal Technology names a Delta faucet technology family, not one universal cartridge; RP50587 is a prominent DST cartridge but model-specific parts diagrams remain decisive.

Measure before purchase

Direct answer

A faucet labeled DST may point toward RP50587, but DST branding alone does not establish fit. Locate the faucet model, open Delta’s parts diagram, and match the listed cartridge because other Delta single-handle and two-handle ceramic units sit outside RP50587’s application.

Fit facts

What identifies this match

Use these details together. One matching feature does not establish compatibility.

Technology
Diamond Seal Technology
Common service cartridge
RP50587
Valve material
Ceramic sealing surfaces
Primary scope
Selected Delta single-handle kitchen and lavatory faucets
Selection authority
Model-specific Delta parts diagram
Boundary
DST is not a universal-fit specification

Technology name versus part number

Delta uses Diamond Seal Technology across collections. The phrase describes the water-control technology, while RP50587 is a particular replacement cartridge used in specified models.

That distinction matters because search listings often collapse a platform name into a universal fit claim that Delta’s model documentation does not make.

Model relationships

The reliable relationship runs from faucet model to official parts diagram to service number. Collection name and exterior handle shape are weaker identifiers because several collections share styling while using different internal generations.

Generations and aliases

Packaging may abbreviate Diamond Seal Technology as DST. This is an alias for the technology, not a supersession number. If an old diagram lists another cartridge, do not infer RP50587 replaced it unless Delta’s current diagram or support record says so.

Incompatible lookalikes

Older Delta ball-valve repair kits, two-handle stem units, and shower cartridges can all appear in broad cartridge searches. RP50587’s stem profile and body are useful confirmation only after model-level application has been established.

Questions

Before you remove or replace the part

Does every Delta DST faucet use RP50587?

Do not assume so. Confirm the service number in the specific faucet’s Delta parts diagram.

Is DST a part number?

No. It abbreviates Diamond Seal Technology.

Can handle shape identify a DST cartridge?

No. Exterior styling can span internal generations; use the model and parts diagram.