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Product Description
This is a 2" diameter reel for use with 1/4" tape on portable-type open-reel (aka reel-to-reel) tape recorders. I have also seen this size referred to as 2.4" and 62mm.
This will work on larger machines too, but I have only ever seen the 2" size on portable machines. Dimensions for this product were taken directly from the take-up reel from a Condord Sound Camera recorder from 1965.