METRIC
MIL-DTL-38999/21C
10 July 2008
SUPERSEDING
MIL-DTL-38999/21B
11 June 2001
DETAIL SPECIFICATION SHEET
CONNECTORS, ELECTRICAL, CIRCULAR, THREADED, RECEPTACLE,
BOX MOUNTING FLANGE, HERMETIC, HERMETIC SOLDER CONTACTS,
SERIES III, METRIC
This specification is approved for use by all Departments
and Agencies of the Department of Defense.
The requirements for acquiring the product described herein
shall consist of this specification sheet and MIL-DTL-38999.
FIGURE 1. Receptacle, classes N and Y .
AMSC N/A FSC 5935
MIL-DTL-38999/21C
2
Connector dimensions
Shell
size
Shell
size
code
P
± .20
PP
± .20
R1
(see note 3)
R2
(see note 4)
S
± .3
V
max
9 A 3.25
(.128)
5.49
(.216)
18.26
(.719)
15.09
(.594)
23.8
(.937)
21.4
(.843)
11 B 3.25
(.128)
4.93
(.194)
20.62
(.812)
18.26
(.719)
26.2
(1.031)
21.4
(.843)
13 C 3.25
(.128)
4.93
(.194)
23.01
(.906)
20.62
(.812)
28.6
(1.126)
21.4
(.843)
15 D 3.25
(.128)
4.39
(.173)
24.61
(.969)
23.01
(.906)
31.0
(1.220)
21.4
(.843)
17 E 3.25
(.128)
4.93
(.194)
26.97
(1.062)
24.61
(.969)
33.3
(1.311)
21.4
(.843)
19 F 3.25
(.128)
4.93
(.194)
29.36
(1.156)
26.97
(1.062)
36.5
(1.437)
21.4
(.843)
21 G 3.25
(.128)
4.93
(.194)
31.75
(1.250)
29.36
(1.156)
39.7
(1.563)
21.4
(.843)
23 H 3.91
(.154)
6.15
(.242)
34.93
(1.375)
31.75
(1.250)
42.9
(1.689)
21.4
(.843)
25 J 3.91
(.154)
6.15
(.242)
38.10
(1.500)
34.93
(1.375)
46.0
(1.811)
21.4
(.843)
NOTES:
1. Dimensions are in millimeters.
2. Polarizing position N is shown.
3. Front or rear panel mounting.
4. Front panel mounting only.
5. Inch equivalents are given for information only.
FIGURE 1. Receptacle, classes N and Y - Continued.
MIL-DTL-38999/21C
3
REQUIREMENTS:
Dimensions and configurations: See figure 1. Interface dimensions shall conform to MIL-DTL-38999.
This connector mates with MIL-DTL-38999/26.
Insert arrangements: See MIL-STD-1560.
Part or identifying Number (PIN) example:
D38999/ 21 Y A 35 P N
DoD no. prefix
Specification sheet no.
Class
Shell size code
Insert arrangement
Contact style
Polarizing position
N is required for normal position
MIL-DTL-38999/21C
4
Changes from previous issue. Marginal notations are not used in this revision to identify changes with
respect to the previous issue due to the extent of the changes.
Referenced documents. In addition to MIL-STD-38999, this document references the following:
MIL-DTL-38999/26
MIL-STD-1560
CONCLUDING MATERIAL
Custodians: Preparing activity:
Army – CR DLA - CC
Navy - AS
Air Force - 85 (Project 5935-2008-019)
DLA - CC
Review activities:
Army - AR, MI
Navy - EC, MC, OS
Air Force - 19, 99
DLA - IS
NOTE: The activities listed above were interested in this document as of this document. Since
organization and responsibilities can change, you should verify the currency of the information above
using the ASSIST Online database at http://assist.daps.dla.mil.
