Micro SIM card is also known as 3rd form factor (3FF). The card measures only 12mm x 15mm (.472" x .59") and has a 0.76mm (.029") thickness.
Contact arrangement is identical to the standard Mini card. Micro cards use the same size and position of pads as Mini SIM.
Gradconn's Micro SIM socket options:
Micro SIM Connector Push-Push - CH03-GB is 1.5mm (.059") height, with a normally closed card presence detection switch. It's suitable for 1,500 card insertion cycles with an operating temperature of -40° to 85°C. Available in 6 or 8 contacts.
Micro SIM Connector Push-Pull - CH03-FB is 2.4mm (.095") height, a half metal shell ensures good contact force and provides protection against warping of the SIM card due to heat. It is suitable for 5,000 card insertion cycles with an operating temperature of -40° to 85°C. Available in 6 or 8 contacts.