Bose 601 Series III speakers (1986-1994) found in a thrift store. They are very sought after and are worth $1k to $1.5k online! They sound great. : r/ThriftStoreHauls
Amazon.com: Replacement Speaker for Bose 4.5" Full Range Speaker 1ohms : Electronics
Replacement Speaker For Bose 4.5" 801, 802, 901 Full Range Speaker 1Ω | eBay
Replacement Speaker Driver for Bose 901 4-1/2" 1 Ohm
SS Audio Recone Kit Compatible with Bose 901, Bose 802, 1 Ohm, RK-B901 - Walmart.com
Bose 801 Speakers w/ Crossover Unit for Sale in Carson, CA - OfferUp
Bose 802 series III technical review why there are PTC there - YouTube
Collectibles Shop's How To Order info | Speakers for sale, Vintage speakers, Speaker design