SQUARE FLAT                                            IFI

Nominal Size

Recess Square(M)

Recess Depth(T)

Driver Size

Penetration Gaging Depth(A)

Max

Min

Max

Min

Max

Min

3

.071

.0696

.073

.063

0

.038

.032

4

.071

.0696

.073

.063

0

.038

.032

5

.091

.090

.113

.105

1

.065

.057

6

.091

.090

.113

.105

1

.065

.057

7

.091

.090

.113

.105

1

.065

.057

8

.1126

.111

.140

.119

2

.075

.065

10

.1126

.111

.140

.119

2

.075

.065

12

.133

.1315

.165

.155

3

.095

.085

1/4

.133

.1315

.165

.155

3

.095

.085

5/16

.191

.1895

.201

.191

4

.100

.090

3/8

.191

.1895

.201

.191

4

.100

.090