Oval Head                                                  ANSI/ASME B18.6.3 1972

Nominal Size

Head Dimensions

Slot Dimensions

Recess Dimensions

Protrusion Above Gaging Dia.

Gaging Dia.

Driver Size

Diameter

Height

Width

Depth

Dia.

Depth

Width

Side

Total

Max

Min

Max

Max

Max

Min

Max

Min

Ref

Ref

Ref

Max

Min

0

.112

.096

.035

.056

.023

.016

.030

.025

.068

.036

.014

.047

.031

.078

0

1

.137

.120

.043

.068

.026

.019

.038

.031

.070

.039

.015

.053

.035

.101

0

2

.162

.144

.051

.080

.031

.023

.045

.037

.106

.060

.018

.058

.039

.124

1

3

.187

.167

.059

.092

.035

.027

.052

.043

.118

.072

.019

.064

.044

.148

1

4

.212

.191

.067

.104

.039

.031

.059

.049

.130

.086

.019

.069

.048

.172

1

5

.237

.215

.075

.116

.043

.035

.067

.055

.152

.073

.028

.075

.053

.196

2

6

.262

.238

.083

.128

.048

.039

.074

.060

.172

.092

.030

.080

.057

.220

2

8

.312

.285

.100

.152

.054

.045

.088

.072

.186

.107

.031

.091

.066

.267

2

10

.362

.333

.116

.176

.060

.050

.103

.084

.202

.125

.033

.102

.075

.313

2

12

.412

.380

.132

.200

.067

.056

.117

.096

.264

.140

.038

.113

.084

.362

3

1/4

.477

.442

.153

.232

.075

.064

.136

.112

.284

.160

.040

.129

.095

.424

3

5/16

.597

.556

.191

.290

.084

.072

.171

.141

.384

.226

.065

.155

.117

.539

4

3/8

.717

.670

.230

.347

.094

.081

.206

.170

.404

.245

.068

.182

.139

.653

4

7/16

.760

.715

.223

.345

.094

.081

.210

.174

.416

.257

.070

.195

.150

.690

4

1/2

.815

.765

.223

.354

.106

.091

.216

.176

.430

.271

.071

.212

.163

.739

4

                                                        Undercut Oval Head                                          ANSI/ASME B18.6.3 1972

Nominal Size

These lengths or Shorter are Undercut

Head Dimensions

Slot Dimensions

Recess Dimensions

Protrusion Above Gaging Dia.

Gaging Dia.

Driver Size

Diameter

Height

Width

Depth

Dia.

Depth

Width

Side

Total

Max

Min

Max

Max

Min

Max

Min

Max

Min

Ref

Ref

Ref

Max

Min

0

1/8

.112

.096

.025

.046

.033

.023

.016

.028

.022

.068

.036

.014

.047

.031

.078

0

1

1/8

.137

.120

.031

.056

.042

.026

.019

.034

.027

.070

.039

.015

.053

.035

.101

0

2

1/8

.162

.144

.036

.065

.050

.031

.023

.040

.033

.106

.060

.018

.058

.039

.124

1

3

1/8

.187

.167

.042

.075

.059

.035

.027

.047

.038

.118

.072

.019

.064

.044

.148

1

4

3/16

.212

.191

.047

.084

.067

.039

.031

.053

.043

.130

.086

.019

.069

.048

.172

1

5

3/16

.237

.215

.053

.094

.076

.043

.035

.059

.048

.152

.073

.028

.075

.053

.196

2

6

3/16

.262

.238

.059

.104

.084

.048

.039

.065

.053

.172

.092

.030

.080

.057

.220

2

8

1/4

.312

.285

.070

.123

.101

.054

.045

.078

.064

.186

.107

.031

.091

.066

.267

2

10

5/16

.362

.333

.081

.142

.118

.060

.050

.090

.074

.202

.125

.033

.102

.075

.313

2

12

3/8

.412

.380

.092

.161

.135

.067

.056

.103

.085

.264

.140

.038

.113

.084

.362

3

1/4

7/16

.477

.442

.107

.186

.158

.075

.064

.119

.098

.284

.160

.040

.129

.095

.424

3

5/16

1/2

.597

.556

.134

.232

.198

.084

.072

.149

.124

.374

.214

.064

.155

.117

.539

4

3/8

9/16

.717

.670

.161

.278

.239

.094

.081

.179

.149

.394

.233

.066

.182

.139

.653

4

7/16

5/8

.760

.715

.156

.279

.239

.094

.081

.184

.154

.404

.245

.068

.195

.150

.690

4

1/2

3/4

.815

.765

.156

.288

.244

.106

.091

.204

.169

.416

.257

.070

.212

.163

.739

4