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Tuesday 22 May 2018 at 16:00
Quoted from dothedoo:Early classic Stern flipper plungers are smaller diameter for about 2/3 of their length. Don’t know if this was done to reduce weight or cost though.
Old bally too. They've got that plastic ring around them to make them the right size for the sleeve
Source: http://pinside.com/pinball/forum/topic/reducing-weight-on-coil-plungers#post-4411591