led , ▁and ▁the ▁Th ales ▁M IR AD OR ▁electro - opt ical ▁sensor ▁replaced ▁the ▁Sign aal ▁L IO D ▁opt ron ic ▁director . ▁A ▁D S Q S - 2 4 C ▁h ull - mount ed ▁son ar ▁from ▁Atlas ▁Ele ktr on ik ▁was ▁installed ▁to ▁complement ▁the ▁new ▁tor ped o - launch ▁capabilities . ▁ ▁Arm ament ▁The ▁K ast uri ▁class ' ▁original ▁arm ament ▁was ▁heavily ▁alter ed ▁by ▁the ▁ 2 0 0 9 ▁modern isation ▁as ▁well . ▁The ▁ 5 7   mm ▁B of ors ▁was ▁moved ▁from ▁the ▁a ft ▁to ▁the ▁bow , ▁where ▁it ▁replaced ▁the ▁ 1 0 0 ▁mm ▁gun ▁as ▁the ▁main ▁gun . ▁No ▁new ▁a ft ▁gun ▁was ▁installed . ▁The ▁two ▁manually ▁operated ▁Emer le c ▁ 3 0   mm ▁tw in - bar rel ▁anti - air ▁guns ▁were ▁replaced ▁with ▁ 3 0   mm ▁single - bar rel ▁M SI ▁D S 3 0 B ▁guns . ▁Anti - sub marine ▁capabilities ▁were ▁en hanced ▁by ▁replacing ▁the ▁dated ▁B of ors ▁ 3 7 5   mm ▁anti - sub marine ▁ro cket ▁launch er ▁with ▁two ▁Euro T orp ▁B 5 1 5 ▁triple ▁tor ped o ▁launch ers ▁equ ipped ▁with ▁White head ▁A 2 4 4 - S ▁tor ped o es . ▁ ▁There ▁are ▁conflic ting ▁reports ▁about ▁the ▁Ex oc et ▁anti - ship ▁miss iles . ▁Some ▁sources