The Fuji Hakone Pass allows visitors unlimited rides in the Fuji-Hakone area for three days. The ticket can be purchased at the Odakyu Sightseeing Service Center at Shinjuku Station and Odawara Station, and at Fujikyu Railways’s Otsuki Station and Kawaguchiko Station. The pass gives you the freedom to explore the Fuji area on the Fujikyu bus and railways in addition to allowing you free use of the buses, trains, ropeway, and cruise ships in Hakone. The ticket also includes a discounted round-trip on the Odakyu Lines (between Shinjuku Station and Odawara Station).
For details, please check the official website of the distributor below.

https://www.odakyu.jp/english/passes/fujihakone/