Name: MRL3212-12-500
Brand: Monogram

MRL3212-12-500 decoded
Family	Radial-Lok (Monogram)
Head style	100° flush tension head (source: Monogram drawing MRL3212 Rev AD, title block)
Nominal diameter	3/8" (-12)
Grip	grip range 0.450-0.500" (drawing Table II)
Material	Titanium. Nut: 6Al-4V titanium alloy; screw: Inconel 718; sleeve: 304 stainless steel; expansion sleeve: A286

Decoded from the published numbering scheme; not a claim that this exact dash number is a stocked SKU, and not a certified design authority. Always verify against the controlling drawing, spec, and your stress group.

Series and strength (datasheet)

MRL3210 (low profile protruding head) / MRL3212 (100° flush tension head) · e.g. MRL3212-06-500

Rated shear 75 KSI; 3/16" double shear 4,800 lb min, tensile 1,600 lb min; "up to .006" via unique radial expansion": Monogram catalog comparison chart.

Datasheet (PDF) ↗

MRL3212 grip chart: 3/8" (-12)

15 grips

Every catalogued max-grip dash number at this diameter. Stack thickness must fall inside the fastener's grip range: see the design calculators.

MRL3212-12-300 MRL3212-12-350 MRL3212-12-400 MRL3212-12-450 MRL3212-12-500 MRL3212-12-550 MRL3212-12-600 MRL3212-12-650 MRL3212-12-700 MRL3212-12-750 MRL3212-12-800 MRL3212-12-850 MRL3212-12-900 MRL3212-12-950 MRL3212-12-1000

Other diameters at this grip:

MRL3212-06-500 MRL3212-08-500 MRL3212-10-500

Expanding sleeve · 3 steps

1/3Inserted, tool placed

“The Radial-Lok fastener is first inserted into the prepared clearance fit hole. The installation tool is placed over the screw, simultaneously engaging the wrench flats and the DRIVE NUT.”

Monogram Radial-Lok brochure, p.2, Installation Sequence ↗

Drawing traced from: Panel 1.

Key (how to read these diagrams)

Manufacturer figure: Monogram Radial-Lok brochure, p.2, Installation Sequence, panels 1-3 ↗Schematic cross-section at the source figure's proportions, not to scale. Terms are the document's own.

Install tooling

Install tooling: MP550RL-12AA (Monogram MRL1003 (Radial-Lok install spec), p.6, Table 1) · proprietary

MGFRL-12 Flush head barrel gage (break-off check)

Radial-Lok tool tables

Decode details

Decode details
Series	Radial-Lok (Monogram)
Decode confidence	high
Numbering source	Monogram drawing MRL3212

MRL3210 and MRL3212 use different grip conventions (see each drawing's grip table); other MRL bases are not decoded.

Government reference cross-reference (DLA FLIS)

not listed under this PN

MRL3212-12-500 is not listed in FLIS under this exact part number (FLIS data as of 2025-03-18, March 2025 snapshot). FLIS may record it with a material or finish code, or under the standard part number.

Source: DLA PUB LOG ↗. Search any part number in the decoder.

Cross-reference MRL3212-12-500

Lead-time risk for this family (SpecLok sourcing assessment): High

Supply signal

not in FLIS by this PN; no SpecLok quotes yet

Supply signalfor this part number

Not listed in FLIS under this exact part number (March 2025 snapshot).
No SpecLok quotes yet.

A signal from records SpecLok holds, not availability, stock or a lead-time promise. FLIS lists who has recorded a part number for the item, not who makes it today. DoD awards carry no NSN or part number, so award activity is for the item name's class.

Sources: DLA FLIS Data Electronic Reading Room (PUB LOG) ↗, DLA PUB LOG ↗, USAspending.gov award search API ↗; DoD award data 2025-10-01 to 2026-07-06; compiled 2026-09-28.