9=pins
four
9
9
9
9
9-pins 9 pins at one end and 4 or 6 at the other. (pg. 407)
9 pins
Basic number is 9 pins, while 24 pins give a higher quality print.
Usually, in the mid 1980's, 9 to 18, or even 24. Apple brought one out with 27 pins for superior printing results.
It is the same as usual except that if you knock 9 pins down it is considered a strike.
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