Machined 1-piece PTFE Core Tube for MK6 1.75 mm filament

All-new machined 1-piece PTFE barrel for MK6 and MK6+ 1.75 mm filament This is a new, single-tube version of the 1.75 mm coretube was designed to enhance the performance of the MK6 and MK6+ Stepstruder when printing 1.75 mm filament. It's a new, specially-machined, single-piece unit that increases reliability with small-filament setups.