HP Pen - Digital pen - for ENVY x360 Laptop; Pavilion x360 Laptop; Spectre x360 Laptop. Jot, sign, doodle or draw your finest points across with the HP MPP 1.51 Pen. A Microsoft compatible pen with two customizable buttons, pen-point accuracy and long 18-month battery life. This natural, true-to-life feel pen will practically make your point for you.