▁a ▁horse ▁in ▁ground ▁training , ▁yet ▁it ▁is ▁a ▁relatively ▁gentle ▁piece ▁of ▁equipment . ▁ ▁Ser re ta : ▁ ▁A ▁type ▁of ▁nose band ▁built ▁into ▁a ▁hal ter ▁or ▁brid le , ▁made ▁of ▁metal ▁and ▁usually ▁with ▁one ▁or ▁three ▁rings ▁pro tr ud ing ▁out ward . ▁ ▁Because ▁it ▁is ▁heavy , ▁it ▁commonly ▁is ▁supported ▁with ▁a ▁fr ent era . ▁ ▁The ▁ser re ta ▁sometimes ▁is ▁stud ded ▁inside . ▁ ▁It ▁is ▁most ▁commonly ▁seen ▁in ▁the ▁I ber ian ▁pen ins ula ▁and ▁Hung ary . ▁Stud ded : ▁a ▁stud ded ▁cav ess on ▁has ▁round ▁or ▁sharp ▁stud s ▁on ▁the ▁inside . ▁This ▁cav ess on ▁is ▁most ▁common ▁in ▁I ber ia , ▁especially ▁on ▁young ▁horses , ▁so ▁as ▁not ▁to ▁" sp o il " ▁their ▁mouth s , ▁and ▁in ▁Aust ro - H ung aria . ▁They ▁have ▁also ▁been ▁adopted ▁in ▁other ▁discipl ines ▁as ▁a ▁means ▁of ▁cont rolling ▁a ▁difficult ▁horse , ▁or ▁as ▁a ▁training ▁shortcut , ▁but ▁they ▁are ▁generally ▁illegal ▁in ▁most ▁horse ▁show ▁competition . ▁ ▁Bl unt ▁stud s ▁have ▁a ▁relatively ▁m ild ▁effect . ▁Sh arp ▁stud s , ▁like ▁a ▁ser r ated ▁kn ife , ▁are ▁extremely ▁pain ful ▁and ▁can ▁cut ▁the ▁horse . ▁When ▁used ▁while ▁r iding , ▁they ▁act ▁with ▁the ▁normal ▁action ▁of ▁the ▁nose band , ▁which ▁applies ▁pressure ▁to ▁the ▁nose ▁when ▁the ▁horse