This is the new style connector from Dell, part number 0KXTTW which still has a pin in the centre of the charger connection,  but is half the size of its predecessors, just check pictures. The Dell power charger listed runs at 19.5v 2.31a and has 45w power and the actual micro tip size is 4.5mm * 3mm

Genuine Dell 0KXTTW ac adapter specification
Ac adapter power: 45w
Power output: 19.5v 2.31a
Power input: 100-240v
Tip pin size: 4.5mm* 3mm (pin in centre) Dells new micro size
Dell part numbers: 0KXTTW, GKJYK, 0GKJYK, 00285k, HA45NE1-00, DA45NM131, 04H6NV, ADP-45XD, JT9DM, FA45NM160, FA45NE1-00, 0JT90M, A-0045ADU00-201, PA1M10 Family, HA45NM140, A045R003L, 0XG0WK, 3RG0T, LA45NM121, PA-1450-66D1 and many more
Dell Ac adapter warranty: 12months
Contents: Brand new genuine 45w Dell charger & plug

• Key points of this Dell 0KXTTW charger
• Next day delivery on orders before 3pm
• UK supplier with UK stock
• Free mains power cable plug
• 12 months warranty as standard
• Genuine Dell small connector charger
• Pin size micro smaller than standard Dells
• Original dell 45w charger

This Genuine Dell 0KXTTW charger is supplied with battery charging unit and mains power cable lead with plug, however if you purchase outside the UK from anywhere in Europe we will send a European 2 pin plug in replacement of the UK version to fit your country of origin.