The LCS / Mesa 4″ titanium tweeter is a top grade high frequency driver ideal for bass guitar speaker application. Made in the USA. The 1″ diaphragm is made of titanium for unparalleled strength and resilience. Requires a 3.5 ” round opening. Screw hole spacing is 3 11/16″. Common in Mesa, Eden and other 210 and 410 bass cabinets.