Name: Hi-Lok
Brand: LISI

Two-sided, pin and collar (threaded): “Manually thread the collar onto the pin.” (Hi-Shear Hi-Lok and Hi-Lok/Hi-Tigue Installation Instructions, p.10, I.1 b)

Shear: 85-95 ksi
Blind bulb: n/a
Install: Both sides needed
Diameters: 5/32, 3/16, 1/4, 5/16, 3/8"
Lead-time risk (SpecLok assessment): Low

Typical applications

·Pin-and-collar structural joints with two-side access

Strengths

+"Collar wrenching device automatically shears off" (HL10 drawing)
+Howmet: "eliminates the need for torque inspection"

Trade-offs

−Needs access to both sides (pin and collar)
−MIL-STD-889C: alloy steel is incompatible with graphite; titanium is compatible except in sea water

Also called HiLok, Hi Lok, pin and collar. P/N: HL10 / HL18 protruding shear head · HL11 / HL19 100° flush shear head · typical collars HL70, HL79, HL82, HL94, HL97

Datasheet strength: HL10: 6Al-4V titanium, 95,000 psi shear minimum; HL18: alloy steel, 95,000 psi shear (160,000-180,000 psi tensile): Hi-Shear drawings (Hi-Lok Product Specification 342).

Standards

Hi-Lok Product Specification 342
HL pin & collar standards (Hi-Shear)

Materials and galvanic compatibility vs CFRP

Alloy	Shear	vs CFRP	Notes	Source
Titanium	95 ksi	low	6Al-4V (HL10 protruding / HL11 flush)	HL10 drawing: 6Al-4V per AMS4928/4967, 95,000 psi shear min
Alloy steel	95 ksi	high	Alloy steel, 160-180 ksi tensile (HL18 / HL19)	HL18 drawing: 95,000 psi shear (160-180 ksi tensile)

vs CFRP: MIL-STD-889C Table I, graphite column: high = incompatible in all environments; low = compatible except sea-water immersion; unrated = SpecLok has not read a rating for this material.About derived ksi

Derived ksi values are min shear ÷ nominal shank area, computed from the datasheet's lbf/kN figures; the datasheet itself publishes no ksi.

Specs source: Hi-Shear/LISI HL10 & HL18 pin drawings ↗: HL10 (Ti) sheet 1: sizes 1/8"-1", double shear & tension minimums; sheet 2: material, heat treat, part-number code. HL18 (alloy steel): same layout. Lead-time risk is SpecLok's sourcing assessment, not a datasheet value.

4 head styles

Some variants only partly sourced

Not redrawn: no head dimensions for this variant in the documents on file. The data at right is from the cited document.

Protruding shear head

HL10: Titanium: 6Al-4V titanium alloy per AMS4928 or AMS4967, 95,000 psi shear minHi-Shear HL10 drawing, title block, sheet 2 ↗
HL18: Alloy steel per AMS6415, AMS6349 or AMS6382, AMS6322; 95,000 psi shearHi-Shear HL18 drawing, title block ↗

Sizes and grip: First dash = nominal dia in 1/32nds; second dash = max grip in 1/16ths (HL10 sheet 2).

Source: Hi-Shear HL10 drawing, title block ↗

Pins verified from Hi-Shear drawing title blocks. Other HL pin numbers exist but are not decoded here.

Head styles (manufacturer terms)

Protruding shear head (HL10, HL18)
100° flush shear head (HL11, HL19)
Protruding tension head (HL12, HL20)
100° flush MS24694 tension head (HL21)

Elevation of a pin.US 2,940,495, Lock nut with frangible driving portion (Wing, Hi-Shear Rivet Tool Co.), Fig. 1 ↗ · US patent drawingWhy this family: Later patents (e.g. US 5,305,666) state the basic Hi-Lok fastener is disclosed in US 2,940,495, G. S. Wing, assigned to Hi-Shear Rivet Tool Co., 1960.

Elevation of a collar. — Elevation of a pin.US 2,940,495, Lock nut with frangible driving portion (Wing, Hi-Shear Rivet Tool Co.), Fig. 1 ↗ · US patent drawingWhy this family: Later patents (e.g. US 5,305,666) state the basic Hi-Lok fastener is disclosed in US 2,940,495, G. S. Wing, assigned to Hi-Shear Rivet Tool Co., 1960.

Compare every family's mechanism

Official manufacturer install demonstration: Hi-Lok installation.

Installation verification and preload

Installed preload

Preload force is not published. What is published is the collar wrenching-hex torque-off range per size, the mechanism that sets preload: e.g. HL86 CRES tension collar -6: 40-50, -8: 110-130, -10: 200-250 (Hi-Shear collar standard sheets, Hi-Lok Product Specification 345). Howmet: the design "cannot be over-torqued... eliminates the need for torque inspection."

What to check after install

The collar wrenching hex must have sheared off cleanly; the remaining collar portion is the installed configuration shown on the standard sheets.
Pin protrusion and collar-seating gap limits are not published at the manufacturer level; quantitative limits live in the airframer's process spec or SRM.

Check gauges (1) and sources.Details

None published by the manufacturer; torque inspection is designed out by the shear-off hex.

Sources: HL86 collar sheet · HL18 pin drawing · Howmet Hi-Lok system. Acceptance limits belong to the controlling spec; verify against your program's process documentation.

Print a shop verification card for the floor

Tool: Hex key (holds the pin) and collar driver (Howmet Hi-Lok system)
Special / proprietary: Standard tooling
Training: Not stated in the cited documents.
Inspection: Collar wrenching hex sheared off (see verification below).

HL10 drawing, "after assembly" view: "Collar wrenching device automatically shears off". Howmet: the design "cannot be over-torqued" and "eliminates the need for torque inspection".

The published install tool and nose for each size, other access options, and the gauges that check the install, from the manufacturer's own tool tables.

Dia.	Tool	Other access	Gauges
-5	Not in the published table for this size	None published	None published
-6	Not in the published table for this size	None published	None published
-8	Not in the published table for this size	None published	None published
-10	Not in the published table for this size	None published	None published
-12	Not in the published table for this size	None published	None published

Full tool tables, envelopes, clearances and source notes Compare tooling burden across all 25 families

Hi-Shear Hi-Lok Installation Instructions, K. Removal of Installed Fastener

“In non-interference fit holes, Hi-Loks can be removed with common hand tools in a manner similar to removing a nut from a bolt. Use an Allen hex wrench to prevent the pin from rotating while the collar is being unscrewed with pliers. If not damaged during collar removal, the Hi-Lok pin can be reused.” Hi-Shear Hi-Lok and Hi-Lok/Hi-Tigue Installation Instructions, p.11, K.1 Common Tools ↗
“To more easily remove Hi-Lok collars from pins installed in interference fit holes and in limited access areas, the HLH128 series of hand tools are available in individual sizes or in sets as in the HLK10 Hi-Lok/Hi-Tigue Collar Removal Tool Kit. The Hi-Lok pin can be reused.” Hi-Shear Hi-Lok and Hi-Lok/Hi-Tigue Installation Instructions, p.12, K.2 and K.3 ↗
“In interference fit holes, ALUMINUM Hi-Lok/Hi-Tigue collars can be removed with an HLC1 Hi-Lok Collar Removal Tool fitted to a 3/8 square socket drive and companion air motor. The tool is pressed firmly over the Hi-Lok Collar and rotated until the tool teeth bite sufficiently into the collar material to grip and unscrew the collar from the pin.” Hi-Shear Hi-Lok and Hi-Lok/Hi-Tigue Installation Instructions, p.12, K.2 and K.3 ↗
“Designed for production use to remove Hi-Lok collars from pins, pistol grip power drivers with cutter-type nosepieces are available. The Hi-Lok pin can be reused.” Hi-Shear Hi-Lok and Hi-Lok/Hi-Tigue Installation Instructions, p.13, K.4 Collar Removal Drivers ↗

Cautions

“NOTE: Initial loosening of the -8 and larger Hi-Lok collars with the HLH128 Removal Tool is recommended.” Hi-Shear Hi-Lok and Hi-Lok/Hi-Tigue Installation Instructions, p.12, K.2 and K.3 ↗

None of the removal procedures on file gives a composite-specific removal caution. The Monogram specs address composite at the hole instead: holes "reasonably round and free from burrs (metallic structure) and delamination (graphite/epoxy type structure)" (MBF2003 §5.1).

HL10
Diameters 5/32", 3/16", 1/4", 5/16", 3/8" · 15 grip lengths
Every dash number Plan grips for your stack
HL11
Diameters 5/32", 3/16", 1/4", 5/16", 3/8" · 15 grip lengths
Every dash number Plan grips for your stack
HL18
Diameters 5/32", 3/16", 1/4", 5/16", 3/8" · 15 grip lengths
Every dash number Plan grips for your stack
HL19
Diameters 5/32", 3/16", 1/4", 5/16", 3/8" · 15 grip lengths
Every dash number Plan grips for your stack

Manufacturer: LISI
Category: Pin and collar

Datasheet (PDF) ↗
Manufacturer page ↗
Hi-Shear/LISI HL10 & HL18 pin drawings ↗: HL10 (Ti) sheet 1: sizes 1/8"-1", double shear & tension minimums; sheet 2: material, heat treat, part-number code. HL18 (alloy steel): same layout.

Find the part number for your stack

HeadDiameterStack thickness, in

Enter your stack thickness and diameter to get the HL10 dash number.

Dash numbers and grips: Hi-Shear HL10 drawing (Code note) ↗

QtyInclude install tooling

Sourcing

Lead-time risk (SpecLok sourcing assessment): Low

Get quotes: SpecLok sources this from authorized distributors and returns price, lead time and certs.You buy from the authorized distributor, who is named on your returned quote. SpecLok is free for buyers.

Supply signalfor this family

10,235 NSNs carry a part number of this family, recorded by 317 CAGE codes (FLIS, March 2025).
Last DoD award for PIN-RIVET items (FSC 5320): 2026-06-25; 2,535 awards since 2025-10-01.
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.