Also referred to by a variety of other names (e.g. alternator hub, fan extension, cooling deflector, air guide).

No visible part number. They can be found in 3, 5, and 6 mounting hole varieties. Metal or plastic fins. With and without cut-outs for voltage regulator. Research suggests 914-6 would have 6 mounting holes, and no notch for the regulator as that was mounted elsewhere.

Porsche parts catalogs suggest it was shared with 1970-73 911 and 1978-83 911 Turbo.
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