Originally presented in titanium, the Horological Machine No. 4 Thunderbolt is now available in rose gold and titanium. Just unveiled at Baselworld 2012, the HM4 RT (“rose titanium”) is a limited edition of 18 pieces. This is the second limited edition series of HM4 after the WWII fighter-inspired Razzle Dazzle and Double Trouble. I somehow prefer the original titanium look of the HM4, but I’m sure this will find its clients. – SJX