Name: MBF2111-8-1650
Brand: Monogram

MBF2111-8-1650 decoded
Family	Composi-Lok II (Monogram)
Head style	Reduced protruding hex head (source: Monogram drawing MBF2111 Rev AC, title block, Tables I, III, IV, material notes)
Nominal diameter	1/4" (-8)
Grip	max grip 1.650" (grip range 1.600-1.650", MBF2111 Rev AC grip table)
Material	Titanium. Nut: 6Al-4V titanium alloy; screw: A286 CRES; sleeve: 304 CRES; insert: acetal

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.

Dimensions

Dimensions as printed, inches
A	Head hex across flats	.375/.367
D	Nut shank diameter	.2595/.2575
G	Max grip + G: datum to the end of the nut shank	.055(ref)
H	Head height	.090/.083
L	Max grip + L: datum to the end of the screw	.70(ref)
Recom. Hole	Drilled hole	.263/.260

All dimensions (19)

B	Head diameter over the hex corners	.409min
E	SLEEVE and SCREW head diameter (2X)	.2595max
F	SCREW wrench flats, on the tail	.135/.130
R	NUT head-to-shank radius	.030/.010
T	DRIVE NUT hex across flats	.375(ref)
Min Avail. Grip	Min available grip dash	-100
J	Installed blind head diameter	.400min
K	Installed: blind side protrusion	.450max
Break-Off	Screw break-off, measured from the skin surface	+.103/-.000
Tensile	Tensile structural failure, min (lbs)	2100min, lbs
Double Shear	Double shear, min (lbs)	7900min, lbs
Locking Torque	Locking torque, min (in-lbs)	2.5min, in-lbs
Grip limits	Dash 8-1650	1.600-1.650

As printed on MBF2111 Rev AC sheet 1 ↗. Letters match the drawing.

Some features are scaled from the figure, not dimensioned.Scaled features

Scaled from the drawing's figure (not drawing dimensions)

Component / feature	Scaled as	Model (in)
NUTnut nose diameter at its end (diameter)	0.775 x D	.2004
NUTnut nose end, from the datum	0.164 x L - G	-1.8105
NUTnut bore = screw thread crest diameter (diameter)	0.723 x D	.1869
SCREWscrew thread crest diameter (threads not modelled)	0.723 x D	.1869
SLEEVEsleeve bore over the nut nose and the insert (diameter)	0.847 x D	.2189
SLEEVEsleeve bore beyond the insert (diameter)	0.736 x D	.1903
INSERTinsert outside diameter (= sleeve bore)	0.847 x D	.2189
INSERTinsert inside diameter (= sleeve bore beyond the insert)	0.736 x D	.1903
INSERTinsert end, from the datum	0.371 x L - G	-1.9446
SLEEVEcrimp line (start of the crimped band), from the datum	0.726 x L - G	-2.1733
SCREWscrew head top (sleeve end), from the datum	0.829 x L - G	-2.2394
SCREWscrew head corner radius	0.062 x E	.0161
SLEEVEsleeve top, from the datum (where the scaled nose meets the scaled sleeve bore)	0.111 x L - G	-1.7769
NUTnut nose taper (included angle)	angle, as drawn	30.8°
DRIVE NUTdrive nut length	1.065 x T	.3993
DRIVE NUTdrive nut bearing diameter (cone end on the head)	0.741 x T	.2779
DRIVE NUTdrive nut bearing cone (half angle from the axis)	angle, as drawn	29.8°
SCREWscrew tail beyond the drive nut	1.056 x T	.3959
SCREWwrench flats run: tail end to the drive nut (as drawn)	as drawn	.3959

Measured on MBF2111 Rev AC sheet 1 figure at 300 dpi and kept as a ratio to a dimension this part number prints. Figure scale 447.7 px/in, fitting row -11, taken from D and E; checked against T (+0.1%), F (-0.9%), L - G (-0.6%).

Also printed in MBF2111 Rev AC for this part

Recommended hole	.260-.263 in (MBF2111 Rev AC sheet 1)
Installed blind head	J .400 in min diameter (MBF2111 Rev AC sheet 1)
Installed protrusion	K .450 in max (TYPICAL INSTALLATION) (MBF2111 Rev AC sheet 1)
Break-off limits	+.103 -.000 in, measured from the skin surface (MBF2111 Rev AC sheet 1)
Tensile	2100 lbs min (structural failure) (MBF2111 Rev AC sheet 1)
Double shear	7900 lbs min (MBF2111 Rev AC sheet 1)
Locking torque	2.5 in-lbs min (MBF2111 Rev AC sheet 1)
Min available grip	dash -100 (MBF2111 Rev AC sheet 1)
Material and heat treat	NUT: 6Al-4V TITANIUM ALLOY PER AMS-T-9047 STA OR AMS4928 OR AMS4967 HEAT TREATED PER AMS-H-81200 TO 95 KSI SHEAR STRENGTH MINIMUM. MAXIMUM HYDROGEN CONTENT 125 PPM. SCREW: A286 CRES PER AMS5731, AMS5732 OR AMS5737 HEAT TREATED TO 175 KSI TENSILE MINIMUM. SLEEVE: 304 CRES PER AMS5639, FULLY ANNEALED. INSERT: ACETAL PER ASTM-D6778 DRIVE NUT: MILD STEEL (MBF2111 Rev AC material and finish notes)
Finish	( - ) NUT: KAL-GARD ANN-RO #1012 CONVERSION COATING OR PHOSPHATE FLOURIDE PER MONOGRAM SPECIFICATION PS741, MAY BE USED AT MANUFACTURER'S OPTION. SLEEVE AND SCREW: PASSIVATE PER AMS2700, KAL-GARD ANN-RO #1013 CONVERSION COATING OPTIONAL. INSERT: NONE DRIVE NUT: COLOR GRAY (MBF2111 Rev AC material and finish notes)
Lubricant	SOLID FILM LUBRICANT PER AS5272 TYPE I OR TYPE II. PARAFFIN WAX, OR CETYL ALCOHOL PER AS87132 (AS REQUIRED FOR PERFORMANCE). (SEE FINISH CODE FOR ADDITIONAL RESTRICTIONS). (MBF2111 Rev AC material and finish notes)

Series and strength (datasheet)

MBF2110 · MBF2111 · MBF2112 · MBF2113 · MBF2120 · MBF2121 · e.g. MBF2112-6-500

Rated shear 75 KSI (catalog comparison chart, MBF2112-06-500); 3/16" (-6) double shear 4,600 lb min, tensile 1,400 lb min, all materials & head styles (MBF2003 Table 10A).

Datasheet (PDF) ↗

Section from Monogram drawing MBF2111 Rev AC ↗ sheet 1.Drawing notes

Section drawn from the printed values in Monogram drawing MBF2111 Rev AC sheet 1 (blind fastener, reduced protruding hex head). Letters are the drawing's. Manufacturer nominal: printed values, the mean where only two limits are printed. Hex head seen across the corners: outline at the B corner diameter, dashed lines at the A flats. Section through the axis: NUT, SCREW, SLEEVE, INSERT and DRIVE NUT as the drawing names them, each hatched on its own. Max grip 1.650 plus G .055 and L .70. The drive nut is cut through its hex corners, as the figure draws it; T is across the flats (dashed). Features the drawing shows without a dimension (nut nose, sleeve start and bores, insert, screw thread, screw head length and corner, crimp line, drive nut length and cone, tail length) are scaled from MBF2111 Rev AC sheet 1 figure and are not drawing dimensions; the INSERT is all scaled (dashed outline). Threads not modelled.

Model: Monogram drawing MBF2111 Rev AC

Envelope model, not manufacturer CAD.Model details

MBF2111-8-1650, manufacturer nominal. Simplified component model from Monogram drawing MBF2111 Rev AC sheet 1. Manufacturer nominal: printed values, the mean where only two limits are printed. Flush heads hold the printed head angle; the head depth is derived. Not manufacturer CAD. Verify against the current drawing before use. One named solid per component as the drawing calls them out (NUT, SCREW, SLEEVE, INSERT and, where the drawing has one, DRIVE NUT). Features the drawing shows without a dimension are scaled from its figure and listed as scaled in the STEP header; threads are not modelled. Axis +Z, head up, z = 0 at the face the head bears on. STEP (AP214) is in inches; STL has no units and is written in millimetres.

Other head styles, same diameter and grip

MBF2110-8-1650 low profile protruding head
MBF2112-8-1650 100° flush head
MBF2113-8-1650 130° flush head

MBF2111 grip chart: 1/4" (-8)

33 grips

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

Other diameters at this grip:

MBF2111-5-1650 MBF2111-5.5-1650 MBF2111-6-1650 MBF2111-6.5-1650 MBF2111-7-1650 MBF2111-8.5-1650 MBF2111-9-1650 MBF2111-10-1650 MBF2111-11-1650 MBF2111-12-1650

Exploded view of the fastener.US 4,457,652, Composite buckling blind fastener (Pratt), Fig. 6 ↗ · US patent drawingWhy this family: Monogram's US 10,267,347 states: "the original Composi-Lok fastener is described in U.S. Pat. No. 4,457,652" (John D. Pratt, 1984; later assigned to Monogram). Shows the original Composi-Lok, not the Composi-Lok II drive-nut version.

Axial cross-sectional view of the assembled fastener prior to installation. — Exploded view of the fastener.US 4,457,652, Composite buckling blind fastener (Pratt), Fig. 6 ↗ · US patent drawingWhy this family: Monogram's US 10,267,347 states: "the original Composi-Lok fastener is described in U.S. Pat. No. 4,457,652" (John D. Pratt, 1984; later assigned to Monogram). Shows the original Composi-Lok, not the Composi-Lok II drive-nut version.

Install tooling

Install tooling: MP550BFP-8AA (Monogram MBF2003 Rev AG (Composi-Lok II install spec), p.4, Table 1) · proprietary

MGPCL Protruding head leaf gage (break-off check)
RM3122-08 Removal nose piece module, protruding hex

Composi-Lok II tool tables

Decode details

Decode details
Series	Composi-Lok II
Decode confidence	high
Numbering source	Monogram drawing MBF2111 Rev AC, title block, Tables I, III, IV, material notes

Composi-Lok II grips: "incremental 0.050\" grip lengths" (MBF2003 §2.1); the grip dash is the max grip, e.g. -300 covers .250-.300" (MBF2110/2112/2113 drawings, grip table).
Diameter dash per the drawing's basic-dimensions table (e.g. -6 = 3/16").
Suffix "A" "designates dual drive nut system for robotic installation" (MBF2112 drawing note 1); MBF2003's installation tooling "not applicable to Composi-Lok II which have an 'A' suffix" (MBF2003 §1.1).

Government reference cross-reference (DLA FLIS)

not listed under this PN

MBF2111-8-1650 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 MBF2111-8-1650

Composi-Lok II by Monogram, blind bolt
Datasheet (PDF) ↗
Manufacturer page ↗
Numbering: Monogram drawing MBF2111 Rev AC, title block, Tables I, III, IV, material notes ↗
Geometry: MBF2111 Rev AC ↗

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.