FF-B-561
Mil spec FF-B-561 includes lag bolts having either a square head or a hex head. Type I – Gimlet point, screw thread
Type II – Cone point, screw thread
Type III – Cone point, fetter drive thread
Style 1 – Hex head
Style 2 – Square head FF-B-588
Mil Spec FF-B-588 covers toggle bolts and screw expansion sleeves. Type I – Spring-wing toggle bolts, with two-piece wings
Class A – Sheet metal winds
Style 1 – Machine screw
Style 2 – Continuous thread stud
Style 3 – Eyebolt Class B – Wing wings
Style 1 – Machine screw
Style 2 – Continuous thread stud Type II - Tumble-wing toggle bolts, with one-piece sheet metal wings
Class A - Pivoted bolts
Style 1 – Machine screw
Style 2 – Continuous thread stud
Style 3 – Eyebolt FF-N-836
Mil spec F-N-836 covers cap, castle, hexagon, knurled, slotted, square, welding and single ball seat nuts. Type I – Nuts, square
Style 1 – Regular
Style 2 – Heavy
Style 3 – Machine screw Type II – Nuts, hexagon
Style 4 – Plain
Style 5 – Jam
Style 6 – Thick
Style 7 – Flat
Style 8 – Flat jam
Style 9 – Heavy flat
Style 10 – Heavy flat jam
Style 11 – Heavy
Style 12 – Heavy jam
Style 13 – Machine screw Type III – Nuts, cap
Style 14 – High crown
Style 15 – Low crown Type IV – Nuts, slotted
Style 16 – Plain
Style 17 – Thick
Style 18 – Heavy Type V – Nuts plain, castle
Type VII – Nuts plain, knurled
Type VIII – Nuts, welding
Style 19 – Without pilot
Style 20 – Pilot Type VIII – Nuts, plain, single ball seat, hexagon FF-P-386
FF-P-386 is superseded by ASME B18.8.1
Mil spec FF-P-386 covers split cotter pins. FF-S-85
Mil spec FF-S-85 for fasteners covers types and styles of slotted and hexagon head cap screws. Type I – Slotted Head
Style 1s – Round head
Style 2s – Flat countersunk head, 82˚
Style 4s – Fillister head Type II – Plain head
Style 10p – Hexagon head FF-S-86
Mil spec FF-S-86 covers socket head cap screw fasteners with optional hexagon and spline socket configurations. Type I – Hexagon socket, cylindrical head, 1936 series. *
Type III – Internal multiple spline socket cylindrical head, 1936 series. *
Type IV – Hexagon socket, flat countersunk head, 82˚ included angle.
Type V – Internal multiple spline socket, flat countersunk head, 82˚ included angle.
Type VI – Hexagon socket, cylindrical head, 1960 series.
Type VII – Internal multiple spline socket, cylindrical head, 1960 series.
Type VIII – Hexagon socket, button head.
Type IX – Internal multiple spline socket, button head.
* Do not use for new design. FF-S-92
Mil spec FF-S-92C covers slotted, cross-recessed and hexagon head machine screws. Type I - Slotted
Style 1s – Round head
Style 2s – Flat head, 82˚
Style 3s – Flat head, 100˚
Style 4s – Fillister head
Style 5s – Fillister head, drilled
Style 6s – Oval bead, 82˚
Style 7s – Truss head
Style 8s – Binding head
Style 9s – Pan head
Style 10s – Hexagon head Type II – Hexagon, plain
Style 10p – Hexagon Type III - Cross-Recessed, Recess Designs I and II
Style 1c - Round head.
Style 2c - Flat head, 82˚
Style 3c - Flat head, 100˚
Style 4c - Fillister head
Style 6c - Oval head, 82˚
Style 7c - Truss head
Style 8c - Binding head
Style 9c - Pan head FF-S-107
Mil spec FF-S-107 covers tooth lock washers for use in assemblies with bolts, studs, and machine screws. Type I – Internal tooth flat
Grade A – Regular
Grade B – Heavy-Duty Type II – External tooth flat
Type III – Internal -external tooth flat
Type IV – External tooth countersunk (80˚- 82˚)
Type V – External tooth countersunk (99˚- 101˚)
Style 1 – Twisted teeth
Style 2 – Teeth with up-and-down bent edges FF-S-111
Mil spec FF-S-111 covers single and double-threaded wood screws with round, flat countersunk and oval countersunk heads having slotted or cross-recessed drives. Types I – Single thread
Type II – Double thread Styles:
1s – Round head, slotted drive
1c – Round head, cross-recessed drive
2s – Flat countersunk head, slotted drive
2c – Flat countersunk head, cross-recessed drive
6s – Oval countersunk head, slotted drive
6c – Oval countersunk head, cross-recessed drive FF-S-200
Mil spec FF-S-200 covers hexagon socket and spline socket headless setscrews. Types:
Type I – Hexagon socket, headless
Type II – Spline socket, headless Styles. (Setscrews shall be of the following styles):
Style 1 – Flat point
Style 2 – Cone point
Style 3 – Oval point
Style 4 – Cup point
Style 5 – Full-dog point
Style 6 – Half-dog point FF-S-210
Mil spec FF-S-210 covers set screws: square head (inch) and slotted (inch and metric). Types:
Type I – Square head, inch dimensions
Type II – Slotted headless, inch dimensions
Type III – Slotted headless, metric dimensions Styles. (Setscrews shall be of the following styles):
Style 1 – Flat point
Style 2 – Cone point
Style 3 – Oval point
Style 4 – Cup point
Style 5 – Full-dog point
Style 6 – Half-dog point FF-W-84
Mil spec FF-W-84 is for (spring) lock washers. This spec covers a helical spring type washer for us with nuts, bolts, screws, and studs to prevent them from loosening. FF-W-92
Mil spec FF-W-92 covers plain, flat washers. Type A – Round washer
Type B – Square wash FF-W-100
Mil spec FF-W-100 covers tooth lock washers for use in assemblies with bolts, studs and machine screws. Type I – Internal tooth flat
Grade A - Regular
Grade B – Heavy duty Type II – External tooth flat
Type III – Internal-external tooth flat
Type IV – External tooth countersunk (80˚-82˚)
Type V – External tooth countersunk (99˚-101˚)
Style 1 – Twisted teeth
Style 2 – Teeth with up-and-down bent edges MIL-DTL-1222, MIL-S-1222, and MIL-B-857
MIL-B-857 is superseded by MIL-S-1222; MIL-S-1222 is superseded by MIL-DTL-1222
Mil spec MIL-DTL-1222 covers standard studs, hex cap screws, and heavy hex bolts in nominal standard diameters of ¼ inch to 4 inches, nuts in nominal standard diameters of ¼ inch to 3 inches, and socket head cap screws in nominal standard diameters of ¼ inch to 1½ inches for applications where a high degree of reliability is required. MIL-DTL-1222 covers a variety of materials, including: Nickel Alloys, Corrosion Resistant Steels (CRES), Titanium, and Aluminum. Studs
Type I – Full body
Type II – Reduced body
Type III – Constant strength body
Type IV - Continuous thread (bolt-stud) Bolts
Type II – Heavy hex
Type III – Heavy hex structural Screws
Type I – Hex cap
Type II – Socket head cap Nuts
Type I – Hex
Type II – Hex jam
Type III – Heavy hex
Type IV – Heavy hex jam
Type V – Hex slotted MIL-DTL-18240 and MIL-F-18240
MIL-F-18240 is superseded by MIL-DTL-18240.
Mil spec MIL-DTL-18240 defines the requirements for self-locking elements for use in externally threaded fasteners such as bolts and screws to be used in fasteners with either UNC, UNJC, UNF, UNJF, UNRC or UNRF threads and where the temperatures will not exceed 250°F. It includes three types of self-locking elements:
Type N – Plug/pellet
Type L – Strip
Type P – Patch NASM 25027, MIL-DTL-25027 and MIL-N-25027
MIL-N-25027 is superseded by MIL-DTL-25027; MIL-DTL-25027 is superseded by NASM 25027.
Mil spec NASM25027 covers the requirements for steel, corrosion resistant steel (CRES), aluminum alloy, copper alloy and nickel-copper alloy (Monel 400) self-locking nuts.
250˚F nuts
450˚F nuts
800˚F nuts MIL-F-19700
Mil spec MIL-F-19700 describes the characteristics of nonmagnetic, screw threaded fasteners and related items that are dimensionally in conformance to recognized military and industrial standards. The intent of this specification is to supplement, not supersede, the specifications normally used for the acquisition of threaded fasteners and related items. Bolts
Type I – Round head
Type II – Hexagon head
Type III – Hexagon head, UNC-3A (for use with type V self-locking nuts)
Type IV – Finished neck, countersunk, flat head Machine screws
Type I – Flat head, 82˚, cross recessed
Type II – Pan head, cross recessed
Type III – Fillister head, slotted and drilled
Type IV – Flat head, 82˚, slotted
Type V – Pan head, slotted Wood screws
Type I – Flat head, 82˚, cross recessed
Type II – Round head, cross recessed
Type III – Oval head, cross recessed
Type IV – Flat head, 82˚, slotted
Type V – Round head, slotted
Type VI – Oval head, slotted Lag screws
Type I – Square bolt head
Type II – Slotted countersunk head Studs
Type I – Full body Nuts
Type I – Hexagon, top chamfered, machine screw
Type II – Hexagon, regular finished
Type III – Hexagon, regular finished jam
Type IV – Square, regular
Type V – Hexagon, self locking nylon insert (Class C material only). Cap screws
Type I – Hexagon head Pins
Type I – Split cotter Washers
Type I – Metal, flat, plain, round
Type II – Spring, nonlink lock
Type III – Internal tooth, flat lock
Type IV – External tooth, flat lock MIL-I-8846
Mil spec MIL-I-8846 covers helical coil screw-thread inserts made from formed wire, the inner surfaces of which, after assembly, provide threads as specified. Type I – Coarse thread
Class 1 – Free running
Class 2 – Screw locking (self-locking) Type II – Fine thread
Class 1 – Free running
Class 2 – Screw locking (self-locking) Type III – Taper pipe thread
Class 5 – NPT pipe thread
Class 6 – ANPT pipe thread Type IV – Metric
Class 3 – Staking (spark plug thread) MIL-DTL-32258 and MIL-N-25027/1
MIL-N-25027/1 is superseded by MIL-DTL-32258.
Mil spec MIL-N-25027 covers the requirements for nickel-copper alloy (Monel 400 and 405), self-locking heavy hex nuts. MIL-P-10971
Mil spec MIL-P-10971 covers tubular-shaped spring pins constructed to resist reduction in pin diameter by means of spring action. Type I – Slotted
Type II – Coiled Classes:
Class 1 – Heavy duty
Class 2 – Standard duty
Class 4 – Light duty MIL-P-16610
Mil spec MIL-P-16610 covers carbon, alloy and corrosion-resisting steel taper pins. MIL-P-21143
Mil spec MIL-P-21143 covers solid, cylindrical, steel, headless straight pins, which are commonly referred to as dowel or machine pins. MIL-PRF-907F
Mil spec MIL-PRF-907F covers antiseize compound for use on threads of steel nuts, studs, bolts and other mating surfaces, including those of superheated steam installations, at temperatures up to 1050 degrees Fahrenheit (°F) (566 degrees Celsius (°C)). MIL-S-21472
Mil spec MIL-S-21472 covers hexagon socket-head shoulder screws and slotted-head shoulder screws. MIL-S-24149
Mil spec MIL-S-24149 covers studs for welding with stud welding equipment and arc shields (ferrules) for shielding studs where applicable. | 
