Complex sentence: Typical low cost crystal cartridges of the 1950s tracked at 5-8 grams of force and used replaceable osmium tipped steel styli called "needles", which styli might last only five to ten plays before needing replacement.
Split into simpler sentences: Typical low cost crystal cartridges of the 1950s tracked at 5-8 grams of force and used replaceable osmium tipped steel styluses called "needles". These styluses might last only five to ten plays before needing replacement.