Round Head Machine Screws: Size Chart & Specifications

 Round Head Slotted and Phillips Machine Screws Drawing

Round Head Machine Screws - Slotted & Phillips Drive Size Chart

Nominal Size

 A H J T M G N

Phillips
Driver
Size
Head Diameter
 Height of Hand Width of Slot Depth of Slot Dimensions of Recess
Diameter Depth Width
Max Min Max Min Max Min Max Min Max Min Max Min -
2 .182 .146 .069 .059 .031 .023 .048 .037 .100 .087 .053 .017

1
3 .187 .169 .078 .067 .035 .027 .053 .040 .109 .096 .062 .018 1
4 .211 .193 .086 .075 .039 .031 .058 .044 .118 .105 .072 .019 1
5 .236 .217 .095 .083 .043 .035 .063 .047 .154 .141 .074 .027 2
6 .260 .240 .103 .091 .048 .039 .068 .051 .162 .149 .084 .027 2
8 .309 .287 .120 .107 .054 .045 .077 .058 .178 .165 .101 .030 2
10 .359 .334 .137 .123 .060 .050 .087 .065 .195 .182 .119 .031 2
12 .408 .382 .153 .139 .067 .056 .096 .073 .249 .236 .125 .032 3
1/4 .472 .443 .175 .160 .075 .064 .109 .082 .268 .255 .147 .034 3
5/16 .590 .557 .216 .198 .084 .072 .132 .099 .308 .295 .187 .040 3
3/8 .708 .670 .256 .237 .094 .081 .155 .117 .387 .374 .228 .064 4
1/2 .813 .766 .355 .332 .106 .091 .211 .159 .416 .403 .205 .068 4

 

 Round Head Combination Drive Machine Screw Drawing 

Round Head Machine Screws - Combination Drive size Chart

Nominal Size

 A H J T M Recess
Penetration
Gaging Depth
  

Phillips
Driver
Size
Head Diameter
 Head
Height		 Slot Width Slot Depth Recess
Diameter
 -
Max Min Max Min Max Min Max Min Ref Max Min
6 .260 .240 .103 .091 .048 .039 .068 .051 .155  .073  .045 2
8 .309 .287 .120 .107 .054 .045 .077 .058 .171  .090  .064 2 
10 .359 .334 .137 .123 .060 .050 .087 .065 .188  .108  .082 2 
1/4 .472 .443 .175 .160 .075 .064 .109 .082 .261  .130  .104 3 
5/16 .590 .557 .216 .198 .084 .072 .132 .099 .301  .170  .144 3 
3/8 .708 .670 .256 .237 .094 .081 .155 .117 .380  .208  .182 4