Dunlop 204 Medium Wall Medium Knuckle Glass Slide
Jack's Guitarcheology is a Dunlop dealer.
From Dunlop:
This glass knuckle slide provides a warm, thick tone that accentuates the middle harmonics of your sound, featuring medium wall thickness and a medium diameter.
Size: 10.5mm
Length: 28mm
Wall: 2.5mm
Inside: 20mm