April 10, 2012 – On February 16, 2012 Malaysia has introduced the third series of coins, themed “Distinctively Malaysia”. The new coins comprise 5, 10, 20 and 50 sen coins and are much lighter and smaller than the previous coins. The 5 and 10 sen coins are made of stainless steel, the 20 sen of a nickel-brass composition, and the 50 sen coins of nickel-brass clad copper.
Because of a distinction by colour and other characteristics they are considered to be more consumer friendly. Furthermore the new coins are more durable and incorporate improved counterfeit resistance security features. A major point in favour of this new series might have been the production cost which is said to be reduced by 49 per cent. The coins feature motifs from traditional crafts, Malaysian flora and fauna and will replace gradually the older coins.
More information on the coins you can read in an article here.
All technical information provides the Central Bank of Malaysia website.