Coins of Netherlands and Netherlands East Indies were minted in the USA from 1942 to 1945 (Hence the S/P mintmark for those years).
According to Krause catalog, the Nederl. Indie 1945 P
Half Cent has two varieties: high P and low P, with the low P somewhat rarer.
(Other denominations have varieties as well but I don't have them.)
At a glance the High P and low P look indifferent:

High P

Low P
But closer inspection reveals the difference:

In High P, the mintmark reaches the top of the ankle, while in Low P, the mintmark does not reach the top of the ankle.
Another way to look at this is that the bottom of mintmark in high P is higher than the rectangle, while in Low P the bottom of the mintmark is as high as the rectangle.