Engineering Dictionary of Terms
"A" "B" "C", "D", "E", "F", "G", "H", "I", "J", "K", "L", "M",
"N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X", "Y", "Z"

COTS Definition

Commercial-Off-The-Shelf. The term Commercial-off-the-shelf [COTS] is defined as any item other than real property that is of a type customarily used by the general public for non-governmental purposes, and that has been sold, leased, or licensed to the general public; is sold, leased, or licensed in substantial quantities in the commercial market place; and is offered to the Government without modification, in the same form in which it is sold, leased, or licensed in the commercial marketplace.

Normally the term COTS is used with regard to Military requirements or military contracts to indicate that military specifications are not required or not to be followed [to save cost]. However components may still be required to operate under military temperature ranges, which would have to be tested for.

Commercial contracts by definition use commercial parts, so are COTS items by definition. COTS does not imply that an item is in stock, but that it is in production but with out regard to lead time. A similar term is Off-The-Shelf [OTS] which means about the same thing [already designed, but may have to be manufactured before sold].

Many times the term COTS/NDI is also used. In this case the COTS portion retains its original meaning, with NDI meaning Non-Developmental Item. Non-Developmental Item means the item has already been designed and requires no additional NRE [Non-Requiring Engineering] to produce it. NDI does not imply that the item is sitting on the shelf waiting to be shipped when ordered. But rather, NDI referees to the fact that an item has been developed, has a part number that can be procured and can be shipped when available, with some amount of lead time.

The Government saves a lot of money using COTS equipment instead of MIL Spec equipment, assuming the equipment or components meet military requirements for temperature and so on. The devices are produced in mass quantities and are not hand tested to QPL, but purchased at the same rate any commercial company would buy them for.

Products qualified to military standards and specifications could be from 2x to 10x the cost of commercial products. In many cases just requiring a component or device to operate over the entire military temperature range will more than double the cost of the item.

Design Hint; Don't spec out a military part unless it's needed to meet your specifications or requirements. In some cases it might be cheaper to purchase a Commercial product and then test that device over the military temperature range to insure the component will still function.

However in rare cases there may be exceptions to the rule of not using a mil spec part without a requirement. For example if a concurrent design or previous product is already using a MIL spec resistor then it may be beneficial to reuse that same part on another product even though it may not require the military part number. Reusing the part may actually reduce production costs by reducing the amount of different parts that need to be ordered and stocked

PC motherboard

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