The EOB putting device

U.S. Patent Number 5,409,228
A visual alignment putting device made of high impact plastic that may be readily attached as a temporary training device or bonded as an integral part of many existing putters that assists the player in visualizing the putting line, in positioning his eyes over the putting line, and in properly aligning the putter head with the ball and in maintaining that alignment throughout the stroke.

Putters with which the EOB putting device can be used

Attachment of the Two-Piece EOB putting device

USGA Ruling On Use of the EOB putting device--Practice and Play

putting device