From 1862 on, the chapel was functioning temporarily as parish church of the quarter Lipótváros dedicated to St. Leopold. The altar of the donators adorned with statuette was designed by József Kauser.
The small, single-banked, pedalled organ of originally 7 and later completed to 9 registers, built by the Gebrüder Rieger Organ Factory of Jagerndorf, was inaugurated on 1st of August, 1894 as a gift from Archbishop György Császka of Kalocsa.
The baptismal font was made from the original plans by Miklós Ybl.
The 14 stations of the Cross were painted by Béla Emmanuel in 1927.
The stained glass windows of Hungarian saints were completed from cartoons by József Pituk Viktorián in the seventies of the XX. century.
The intact Holy Right Hand relic of King St. Stephen was placed on the reliquary altar of the chapel, divided from the vestry, in 1971.
King Stephen died on 15 August 1038, was canonized on 15 August 1083 in Székesfehérvár and his intact Holy Right Hand relic has been highly estemeed ever since. It has had a life of vicissitudes : guarded in Bihar (Transylvania) and Raguza ( today's Dubrovnik in Dalmatia), it was ordered to be brought to Buda by Queen Maria Theresa in 1771 and venerated in the Zsigmond Chapel of Buda Castle up to 1944.
It was fled to be safeguarded from the vicissitudes of the war in the West, and returned to Hungary on 19 August, 1945 to be entrusted to the care of the parish of St. Stephen's Basilica in 1950.
It has been put on display in today's glass case since 1987, protected with a double reliquary. The outer, chapel-shaped shrine was made from József Lippert's design in Vienna, 1862 and the Right Hand relic of the King is encased in a glass cylinder inside.
Founder of our state, King St. Stephen of Hungary is celebrated with a Holy Right Hand procession on 20th of August every year.