Insert overmolding is expensive ?

It is labor-intensive than two-shot overmolding, production cost per part using this technique will be higher, but it eliminates the extremely high cost and delay of producing complex two-shots mold.
If speed to market is critical, it may make sense to use pick-and-place to deliver product to market.
It reduces risk by allowing redesign of molds at a fraction of the cost of remaking two-shots molds.
Production volume-typically under 10,000parts or need to prototype design or test materials or possibility that the design will change is still  economical to use insert overmolding.

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