Drill pen blanks up to 3-1/2"; Compatible with the PENPAL Mini Pen Making Lathe, or other lathes with similar headstock and tailstock mounts. Includes (1) dedicated pen blank drilling lathe chuck, (1) drill chuck, and (1) lathe headstock spindle adapter. Lathe Headstock Spindle Adapter LA3418X converts a 3/4" x 16tpi spindle to 1" x 8tpi; Allows a 3/4" x 16tpi threaded spindle to accept 1" x 8tpi threaded chucks, faceplates, and other woodturning tools and accessories; Weighs .2 lbs. Dedicated Pen Blank Drilling Lathe Chuck CSCPENCHK securely holds pen blanks up to 1" x 1" x 4"; Chuck is pre-threaded to 1" x 8tpi; Weighs 1.2 lbs; Diameter is 2.5"; Jaws are 2" long; Includes (2) tightening levers to open and close the chuck jaws. Drill Chuck PENPALDC mounts in the tailstock with a #1 Morse Taper arbor; Maximum opening is 10 mm; 10 mm = 0.393701".