TO 35C2-3 4144 4
(USMC) Special Stockage Indicator Code and Replacement Factor (Column 3).
(1) Special Stockage Indicator Code (Column 3a). This column reflects the condition under which certain
maintenance parts, (parts assigned NSNs and coded in the "P" series source code of the SMR code), are stocked. The
codes are explained as follows:
Indicates that the part may or may not be authorized in initial allowances to using or supporting organizations.
The manner of determining initial allowances is explained in paragraph (2) below.
Applied to maintenance parts which predicted consumption would not warrant inclusion in Mount-Out but, for
which a quantity of one (1) is authorized as insurance for Mount-Out using a 360-day criterion. This criterion
is based on the total Onsity of equipment employed by the DIV/WING TEAM. Mount-Out allowances, so
authorized, will be stocked by the FSR or the MWSG in the case of MARINE Wing peculiar equipment, as
Applied to maintenance parts that are not considered critical or essential to be on hand and, therefore, are not
authorized in initial allowances; however, these items are stocked within the Supply System and may be
requisitioned based upon usage.
Indicates that the part is authorized in garrison operating allowances in order to comply with state and local
laws; however, the part is not authorized in Mount-Out since it is not combat essential.
(2) Replacement Factor (Column 3b). This column reflects the replacement factor assigned to each National
Stock Number maintenance repair part on its first appearance in the publication. The replacement factor, expressed as a
decimal, indicates the average rate at which the type of item so coded has been used by Marine Corps field units or the
rate at which design engineers anticipate the item will fail, wear out, or otherwise require replacement. All computations
are based on a replacement period of one year. Therefore, a replacement factor of 0.08, applied to an item in this stock
list, indicates that eight out of every one hundred such items used in the end item of equipment to which this publication
pertains, is predicted to need replacement in one year. Likewise, 0.004 reflects that four out of every thousand in use are
predicted to require replacement in one year, while 2.0 shows that every one in use is predicted to be replaced twice
during each year.
(a) Initial authorized stockage levels of consumable and salvageable items for an organization are to be
computed for predicted consumption based on the number of items employed and/or supported by an organization within
the number of days for which stockage is authorized. In computing Garrison Operating Stock or Mount-Out, authorized
levels can be determined by the requiring Marine Corps unit by multiplying the replacement factor times the quantity
used per equipment, times the number of end items employed by the using organization or supported by the service
organization, times the authorized day level expressed in months and divided by 12. Specific formulas and examples
are provided in Marine Corps Order, MCO P4400.79
The replacement factors used in initial stockage computations should be revised, if warranted, after
significant usage is experienced in accordance with the guidelines of MCO 4400.32A. The following formula
replacement factor "X" represents actual usage experience (1 year), "A" represents the application per equipment, and
"B" represents the number of equipments supported.
A x B
(b) Initial allowances for maintenance float items (recoverability codes "R" and "D") for the FMF and
appropriate post and stations are as furnished by Initial Issue Actions.
Changes to maintenance replacement rates resulting from actual usage may require recomputation of
maintenance float allowances by holding units. Any required recomputation of maintenance float allowances will be
made in accordance with MCO 4000.6.
(c) The replacement factor for same as (S/A) items is indicated upon the first appearance of the item in the
major combination, component or assembly.