Abbreviation: SWM = "Silent Wave Motor" (Nikon)

The abbreviation SWM means "Silent Wave Motor" and is seen on Nikon products.

Explanation from Nikon

Nikon´s AF-S technology is yet another reason professional photographers like NIKKOR telephoto lenses. AF-S NIKKOR lenses feature Nikon’s SWM which converts “traveling waves” into rotational energy to focus the optics. This enables high-speed autofocusing that’s extremely accurate and super quiet.

See examples of effected products

	Nikon AF-S 50mm F1.4 G
	Nikon AF-S 200mm F2 G ED VR II
	Nikon AF-S DX 16-85mm F3.5-5.6 G ED VR

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