The kerosang rantai/kerongsang brooch is a set of 3 brooches used by the Peranakan Straits Chinese ‘Nyonyas’ to fasten kebaya/baju panjang. Kebaya top has no button. Kerosang consists of three identical shapes and designs connected with chains. 
 
each flower dimension:
Height: 1.95" / 5cm
Width: 0.80" / 2cm