1 9 8 1 ▁to ▁ 1 9 9 8 . ▁ ▁S kee - B all ▁is ▁now ▁a ▁social ▁sport ▁played ▁in ▁bars ▁in ▁North ▁America , ▁with ▁le agues ▁forming ▁under ▁various ▁b ann ers . ▁ ▁Game play ▁Game play ▁var ies ▁depending ▁on ▁the ▁particular ▁machine ▁but , ▁normally , ▁a ▁player , ▁after ▁inserting ▁appropriate ▁payment , ▁receives ▁a ▁queue ▁of ▁( us ually ▁nine ) ▁balls ▁made ▁of ▁either ▁pol ished ▁m ason ite ▁or ▁heavy ▁pl astic ▁and ▁each ▁approximately ▁three ▁inches ▁in ▁diameter . ▁Each ▁machine ▁has ▁an ▁incl ined ▁r amp , ▁ 1 0 – 1 3 ▁feet ▁long , ▁up ▁which ▁the ▁player ▁must ▁roll ▁the ▁balls . ▁A ▁sudden ▁increase ▁in ▁incl ine ▁at ▁the ▁end ▁of ▁the ▁r amp ▁( called ▁the ▁" ball - h op ") ▁launch es ▁the ▁balls ▁above ▁the ▁plane ▁of ▁the ▁r amp ▁toward ▁a ▁series ▁of ▁rings ▁that ▁direct ▁the ▁balls ▁into ▁holes ▁of ▁varying ▁point ▁values , ▁with ▁the ▁smallest ▁and ▁hard est ▁to ▁reach ▁usually ▁giving ▁the ▁most ▁points . ▁The ▁machine ▁disp enses ▁coup ons ▁to ▁the ▁player , ▁based ▁on ▁scoring ▁th resh olds , ▁either ▁during ▁the ▁game ▁or ▁after ▁the ▁game ▁ends . ▁The ▁coup ons ▁are ▁typically ▁trad ed ▁at ▁the ▁ar cade ▁for ▁pri zes . ▁Some ▁machines ▁award ▁large ▁cou pon ▁bon uses ▁to ▁players ▁who ▁att ain ▁or ▁sur pass ▁a ▁posted ▁high ▁score . ▁ ▁At ▁travel ing ▁car n ival