Runice RNC Extruder Kit — BMG Internals + Push-Fit Fittings + PTFE 300 mm + Black PTFE 1.5 m

Runice's RNC-coated BMG internals plus the fittings, collets, extruder liner and tube that complete the filament path. One bag for a BMG-style extruder rebuild or a new toolhead.

What's in the kit

• 1× Runice RNC-coated BMG internals kit — RNC nano-coated dual-drive gears, black 50T reduction gear, shafts, bearings, spring and thumbscrew (P/N A120-03A)
• 1× PC4-M10 push-fit fitting, black collar — the extruder-side coupler for 4 mm tube
• 2× ECAS04 embedded collet with blue release caps — the toolhead-side tube sockets
• 2× orange collet clips — lock the tube against back-out
• 1× PTFE tube, 2 mm ID × 4 mm OD, 300 mm — the extruder liner: cut it to length for the filament path inside the extruder body. Not every extruder uses a liner, but having it in the bag is what makes this a kit.
• 1× black PTFE tube, 2.5 mm ID × 4 mm OD, 1.5 m — the reverse-bowden run

Which tube

• Black PTFE, 2.5 mm bore × 1.5 m — the standard reverse-bowden tube, in the colour that disappears into a dark build.
• Want to see the filament? The same kit comes with clear FEP; for white PTFE pick the bore: 2 mm, 2.5 mm or 3 mm.

Fits

• Any BMG-style dual-drive extruder body — Voron Clockwork, Afterburner and Mini Afterburner builds and the many printed BMG clones; 1.75 mm filament, 4 mm OD tube.
• Budget option: the same kits with Two Trees BMG clone internals.

Gotchas

• No extruder housing, motor, hotend or fasteners — this is the internals and the filament path.
• ECAS04 needs a housing pocket cut for the embedded collet; the PC4-M10 needs an M10 port.
• Same parts, same shelf as the singles linked above — if the kit reads sold out, one of its parts is.