You really piqued my curiosity. This is the closest I could determine:
EUCHARISTIC CHAPLET OF THE MOST BLESSED SACRAMENT
Said on the beads of the Blessed Sacrament, consisting of a crucifix, five beads and the Most Blessed Sacrament medal. The chaplet starts and ends on the crucifix. Prayers are recited up the five beads, around the medal and back down the five beads. The five beads honor the five wounds of our Lord and Lady.
The chaplet is said by starting and ending with the following prayers, said three times:
I asked the pastor at our my church and he said it is for the chaplet of divine mercy. But then why only 3 decades not 5 or one? Plus I think there are 11 beads in the decades.
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