Tuna Circle hook silhouette
Hook Reference › O. Mustad & Son Hooks › Mustad 39960 ST — Tuna Circle

O. Mustad & Son 39960 ST

Tuna Circle1969 or later

Evidence reviewed September 28, 2026. Marks: P photographically · V verified · I inferred · E estimated · S speculative What they mean

↔ Compare this hookPrint size chart

Save this hook to your account to build a list you can come back to.

Summary

The Mustad 39960 ST Tuna Circle is a saltwater circle hook. Its point turns back to face the shank rather than running parallel to it P.

The entry records one size 8 hook, photographed with a label marked for 100 hooks. The label’s Auburn, N.Y. imprint places it in mid-1969 or later V.

The finish, any point offset, and the relation of the label size to the maker’s modern size scale remain open.

Photographic record

3 photographs

Mustad 39960 ST Tuna Circle — hook profile showing reversed beak point and round/Kendal bend — size 8 — tinned finish on grid
IMG-1Mustad 39960 ST Tuna Circle — Bend Profile — Size 8 Point and barb of the size 8 specimen. The point curves back toward the shank, and the barb is cut at the base of the point section, well back from the tip.

How to identify it

Labels of this issue have a blue upper panel over a cream lower panel. The blue panel carries two tall pointed peaks above a large MUSTAD wordmark, both reversed out in cream P. To the right, a line-drawn key sits between the words KEY and BRAND, with FISH HOOKS below P.

The cream panel has printed headings QUAL., NO. and QTY., divided by vertical rules. The pattern code, size, count and the name Tuna Circle are applied beneath in grey ink, lighter than the black printing P.

Technical profile and measurements

Features of the model, as recorded
FeatureRecordedEvidence
EyeBall Eye, Straight / Inline
Show noteHide note

Closed ring of round wire, set in line with the shank P. Photographed edge-on, so the opening is not visible. A small depression marks the junction with the shank P.

OBS-1
WireExtra-Heavy (2X+), Round
ShankShort (1X–2X Short) — Curved / humpedOBS-2
BendStandard gap
Show noteHide note

Circle form. A short near-straight run behind the eye curves continuously through the bend, and the point section returns to face the shank P.

OBS-2OBS-3OBS-4SRC-1CMP-2CMP-2 compared with 83 catalogued hooks classified Round / Kendal, near the line with Perfect
Point
Show noteHide note

One prominent cut barb on the inner face at the base of the point section, well back from the tip. The cut face and slice line are clearly visible P.

OBS-4SRC-1SRC-2OBS-5
FinishTinned — judged from the photographs
Show noteHide note

Silver-grey coating with a granular texture and darker mottling along the point P. The label states no finish. Tin is inferred from a dealer description of the current hook I.

OBS-6LBL-5LBL-6SRC-2

The label marks the size as No. 8 P. Mustad’s current 39960ST chart runs in /0 sizes, where 8/0 is 28 mm long and 12/0 is 38 mm long V.

The recorded hook is about 38 mm long E. The label’s No. 8 is therefore probably not the same step as a modern 8/0 I.

Mustad describes the current hook as 2X strong, with an inline point V. An inline point lies in the plane of the bend, with no offset to either side. No source documents the wire or point specification of the Auburn-era hooks.

Measurements

Known manufactured size range: Size 8 only V — documented on packaging

Per size, with how each dimension was taken
SizeOverall lengthShank lengthGap widthBend depthWire diameterWeight
8Specimen S137.8 mm EcaliperMEA-118.4 mm Egrid photoMEA-212.5 mm Egrid photoMEA-3—2.4 mm Egrid photoMEA-4 Check: The evidence record measured 2.4 mm (MEA-4).—
Calibrated SVG True-scale preview

How hook dimensions are measuredA hook outline with dimension lines for overall length, shank length, gap, bend depth, and wire diameter.Overall lengthShank lengthGapBend depthWire diameter
Overall length
Eye to the farthest point of the bend.
Shank length
Eye to the start of the bend.
Gap
Point to shank, at right angles to the shank.
Bend depth
Shank to the bottom of the bend.
Wire diameter
Across the wire, measured by caliper where possible.

Specimens, packaging, and label

This record documents one specimen. It describes that specimen only, not every example of the model.

Mustad 39960 ST Tuna Circle label in blue and cream with MUSTAD and Key Brand marks, No. 8, quantity 100
Open full size

S1 · Size 8 hook with Auburn label

Size
8 (printed on the label)
Container
Other
Hook condition
Coating lifted along the barb cut, with a fine crack-like line just behind the barb and light scratches. One or two tiny red-brown specks near the barb, possibly rust or debris. Point tip intact. No heavy corrosion.
Packaging condition
Good — moderate wear, legible
Wear
cream lower panel, overall: Uneven brown toning and speckling across the cream panel, heavier toward the lower edge and corners. LBL-10
Wear
blue upper panel, center and right: Small pale scuffs and specks in the blue ground, including near the letters MUS and above the right peak of the device; faint crease or scuff line near the top right corner. LBL-11
Measured
size 8
Photographs
IMG-1IMG-2IMG-3

Only the label face is photographed. The container, its interior and the hook count are not shown. The photographed hook is probably, not certainly, from this box.

What the label says

LBL-1 printed · blue upper panel, top center from IMG-3
MADE IN NORWAY
FRABRIQUE EN NORVEGE
LBL-2 trademark · blue upper panel, center from IMG-3
MUSTAD
LBL-3 trademark · blue upper panel, right of center from IMG-3
KEY BRAND
FISH HOOKS
LBL-4 printed · blue upper panel, bottom edge from IMG-3
O. MUSTAD & SON (U.S.A.) INC., AUBURN, N.Y. 13021
LBL-5 printed · cream lower panel, field headings from IMG-3
QUAL. | NO. | QTY.
LBL-6 stamp · cream lower panel, under QUAL. from IMG-3
39960 ST
LBL-7 stamp · cream lower panel, under NO. from IMG-3
8
LBL-8 stamp · cream lower panel, under QTY. from IMG-3
100
LBL-9 stamp · cream lower panel, bottom center from IMG-3
Tuna  Circle
Trademark
Two tall pointed peak shapes forming an M-like device above a large MUSTAD wordmark, both reversed out in cream from the blue ground. To the right, a black line-drawn key with KEY BRAND split on either side of the key shank and FISH HOOKS below.
As entered on the specimen record
MADE IN NORWAY
FRABRIQUE EN NORVEGE
MUSTAD
KEY BRAND
FISH HOOKS
O. MUSTAD & SON (U.S.A.) INC., AUBURN, N.Y. 13021
QUAL. | NO. | QTY.
Layout
Blue upper panel carrying the origin lines, trademarks and company imprint. Cream lower panel with three field headings divided by vertical rules, the entries beneath, and the pattern name at the foot.
Typeface
Printed text is black, in bold sans capitals. The field entries and Tuna Circle are in a lighter grey ink in a plain sans style, rubber-stamped or typed.
Printed marks
Applied in grey ink: 39960 ST (under QUAL.), 8 (under NO.), 100 (under QTY.), Tuna Circle (bottom center).

Condition

Hook: coating lifted along the barb cut, a fine crack behind the barb, light scratches, and one or two tiny red-brown specks near the barb P. No heavy corrosion. Label: cream panel toned and speckled; blue panel lightly scuffed P.

Pattern history and manufacturer context

Series

The label gives the pattern as 39960 ST, with the name Tuna Circle P. Mustad’s current reference for the pattern is 39960ST-DT, where DT marks the Duratin finish V. A dealer gives 39960D as an older code V.

ST therefore appears to be part of the pattern code rather than a finish mark I. Mustad lists the 39960ST today in sizes 8/0 to 20/0 V. No period catalog has been found showing which sizes were offered when this label was printed.

Design lineage

Mustad classes the 39960 as a circle hook V. In a circle hook the point turns back toward the shank instead of running parallel to it. No period source has been found recording when the pattern was introduced or what preceded it.

Dating

The label imprint reads O. MUSTAD & SON (U.S.A.) INC., AUBURN, N.Y. 13021 P.
A New York State Tax Commission decision records that this company began business in Auburn on 1 July 1969 V. The label therefore cannot predate mid-1969.
The same decision places the start of consumer packaging at Auburn in the late 1970s V. Whether this label belongs to that period is not established.
No later limit is documented.

O. Mustad & Son — O. Mustad & Son (U.S.A.), Inc. was a wholly owned subsidiary of O. Mustad & Son A/S of Oslo V. At Auburn, New York, it first warehoused hooks shipped in bulk from Norway. It later turned to consumer marketing and did its own sorting and packaging V. Read the maker’s history →

Use

  • Saltwater

Primary application

The label names the pattern Tuna Circle P. Mustad’s current listing presents the 39960ST as a circle hook for tuna, fished by drifting, trolling or kiting V. No period source records how the Auburn-era hooks were used.

Collecting and buying

3 / 10CollectabilityRarity: Common

Rated 3/10 — common, with interest. Mustad still lists the 39960 in its current range, so the model is easy to find V. Boxes with the Auburn, N.Y. imprint add period interest, but no sales or survival counts are recorded for them.

Basis: The model is in current Mustad production (SRC-1). The Auburn company packaged hooks for sale in boxes of 100 and other quantities (SRC-3). No sales records, survival counts or period catalog listings are recorded for Auburn-labeled boxes.

Availability: The pattern remains in Mustad’s current catalog V. The Auburn company that issued this label packaged hooks for sale in several quantities, including boxes of 100 V.

Period interest: Auburn-labeled boxes are the vintage form of the model. No sales, survival counts or catalog listings are recorded for them, so their scarcity is not established.

Market value

Insufficient recorded sales data to estimate a reliable value.

0 sold observations recorded; 2 are needed, with the basis and date of the range, before a value is shown. Asking prices are shown as asking prices only.

No sold results are recorded for this model in period packaging. The value range shown is not supported by recorded sales.

Where to find

Current 39960ST-DT hooks are sold through tackle dealers V. No source records where Auburn-labeled boxes are offered.

Modern equivalents and related hooks

Best matchRelated by Attribute

Computed automatically from catalog data — updated as new hooks are added.

SilhouetteHook ModelMatchAnalysisCompare
3998 G No. 5/0 — Mustad 3998 G silhouette3998 G No. 5/0 — Mustad 3998 G60%Matches: Shank, Wire, Eye Orient., Finish, Forging +1 moreDiffers: Gap: Standard vs Wide; Eye: Ball Eye vs Needle Eye; Application: Saltwater vs Saltwater, Bait +3 moreCompare
7734 No. 10/0 — Mustad 7734 Giant Tuna Hook silhouette7734 No. 10/0 — Mustad 7734 Giant Tuna Hook60%Matches: Shank, Wire, Gap, Eye Orient., Finish +2 moreDiffers: Eye: Ball Eye vs Needle Eye; Forging: Round vs Forged; Application: Saltwater vs Bait, Saltwater +2 moreCompare
10015T No. 8/0 — Pflueger Titan silhouette10015T No. 8/0 — Pflueger Titan55%Matches: Gap, Eye Orient., Finish, Offset, Application +1 moreDiffers: Shank: Short (1X–2X Short) vs Standard; Wire: Extra-Heavy (2X+) vs Heavy (1X Heavy); Eye: Ball Eye vs Needle Eye +3 moreCompare
842,594 — Van Vleck Hook silhouette842,594 — Van Vleck Hook53%Matches: Eye Orient., Offset, Application, BarbDiffers: Shank: Short (1X–2X Short) vs Standard; Wire: Extra-Heavy (2X+) vs Heavy (1X Heavy); Gap: Standard vs Wide +6 moreCompare
9537 No. 6/0 to 2 — Mustad 953753%Matches: Shank, Wire, Finish, BarbDiffers: Gap: Standard vs Wide; Eye: Ball Eye vs Tapered Eye; Eye Orient.: Straight / Inline vs Turned Up +6 moreCompare

Sources, open questions, and record notes

Sources & Documentation

This specimen and its packaging — photographed, 3 images
Supports: bendpointshankconstructionfinishsub brandquantity per packageeyebarbcondition notesoverall lengthshank lengthgap widthwire diameter measuredmeasurement notesdating rangepackagingfun fact titlefun factcollectability summarymeta descriptionprimary search termssummarytechnical notesseries historydesign lineageprimary applicationidentification

Entry last updated September 28, 2026. Entries are updated as new specimens, measurements, or documents come to light.