Universal Engineering WW Double Taper Collet Lot & Chuck Extensions. Collet sizes include: .082, .128-(3), 1/8-(3), 9/64, 5/32, 13/64, 1/4, 9/32, 5/16, 11/32. Long holder has 3/4” straight shank and is part number 55054. Short holder has J2 ID bore taper and is part number 55312. What you see is what you get. Please feel free to check out my other machinist/tool related items, thanks.