OCBC of Malaysia and Singapore released red packets with the same designs. The red packet set comes in four different designs. The colour shade between the Malaysia and Singapore packets is slightly different. Honestly, it is quite difficult to tell apart the different colour shades. The easiest way to differentiate the colour shade is to compare these packets side by side.
However, there is another way to tell apart these packets. You may try to look closely at the back of the packets. The Malaysia packets bare the wording OCBC's red packets, and the Singapore packets have the wording OCBC Bank's red packets (see below image). Now you can check yours to see you have the Malaysia or Singapore packets.