Nike OZ #4 Putter Dual Site Lines: Every OZ putter comes with dual site lines to facilitate consistent squaring of the putter face at address. Milled Faces: Each putter face is milled perfectly flat to enhance accuracy and predictability across the clubface. Face Balanced: All of the OZ mallets are face balanced to promote a square putter face at impact. The ultra lightweight polymer (63% lighter than aluminum) also allows for enhanced perimeter weighting which increases stability through impact. High Visibility Polymer Insert: The green insert color helps to strike the ball with confidence, while the soft polymer keeps the ball in contact longer to promote a true roll and a great feel.