What the Bondtech INDX tool changer is

The Bondtech INDX is a toolchanger in which one powered “Smart Head” carries the extruder, the electronics and an induction coil. It picks up passive nozzle tools that have no heater, thermistor or wires, and heats each one in 4 to 12 seconds. Prusa sells it for the CORE One with up to 8 tools; Bondtech sells the toolhead for Voron and other CoreXY builds at $390 (October 14, 2026 listing).

What is the Bondtech INDX?

The Bondtech INDX (INduction Dynamic eXtruder) is a tool changer for FDM (fused deposition modeling) printers. A single active Smart Head carries the extruder, electronics and an induction coil. It picks up passive tools, each a slim nozzle assembly with its own filament loaded and no heater, thermistor or wiring, and heats the selected nozzle by induction in seconds.

How an INDX tool change works

• What gets swapped. Only the passive tool. The Smart Head stays on the X carriage with the extruder motor, Bondtech’s DX dual-drive extruder, the induction coil and contactless infrared temperature sensing. Bondtech’s GitHub calls it “a true tool changer: each tool carries its own filament directly”, so it is not a filament switcher.
• Coupling and extrusion. A tool attaches to the head by mechanical Maxwell (kinematic) coupling with no electrical contacts. The head’s extruder opens and closes around the filament of whichever tool it holds.
• Timing. Bondtech gives about 14 seconds per tool change, including a 4 to 12 second nozzle heat-up. A parked tool cools in its dock, which Bondtech says limits oozing.
• Limits. Maximum nozzle temperature is 300 °C. Bondtech quotes 40 mm³/s maximum flow, measured at 220 °C.
• On the head. A board built with Duet3D, connected over USB or CAN (Controller Area Network) through an INDX Link Board, plus a load cell for bed probing and a port for an eddy-current scanner coil.
• Tool count. Up to 8 tools on the Prusa CORE One, because that is what fits in the enclosure. The development kit has no fixed limit; dock space sets it. Each dock is about 28.5 mm wide, and tools need at least 34 mm spacing, or 41 mm with part-cooling ducts fitted.

Which printers does INDX fit?

Printer	Status per Bondtech	Sold by
Prusa CORE One / CORE One+	First-party integration, up to 8 tools	Prusa Research only
Prusa CORE One L	First-party integration (listed in Bondtech’s GitHub; the INDX page still says “coming later”)	Prusa Research
Sovol SV08 and SV08 Max	Officially recognized community integration	Bondtech development kit
Voron Trident R2	Officially recognized community integration	Bondtech development kit
Voron 2.4, RatRig V-Core	Unverified community builds	Bondtech development kit

Bondtech says any CoreXY printer with open firmware can take INDX if it meets the motion-system and clearance requirements in its docs. On a Voron, the head mounts with Bondtech’s MGN-12 X-carriage. Team FDM’s August 2026 roundup notes that 2.4 conversions “carry more compromise” than Trident builds, because of the 2.4’s flying gantry. For the other Voron options, see toolchangers for Voron printers.

Does INDX run Klipper or Prusa firmware?

Both, depending on the version. The Prusa CORE One INDX runs Prusa’s own firmware. Its changelog lists version 6.9.2, released October 7, 2026, as the latest. The development kit supports three firmwares, per Bondtech’s GitHub:

• Kalico. Recommended, with native INDX support built in.
• Klipper (mainline). Needs the indx_klipper module installed.
• RepRapFirmware. Version 3.7.0-alpha or later, on both the main board and the toolboard.

How much does INDX cost?

US prices on Bondtech’s store on October 14, 2026, sorted by price:

Item	Price
INDX Tool Dock Hardware Accessories (dock hardware only)	$4.90
INDX MGN-12 X-Carriage (Voron mount)	$9.90
INDX Tool Dock 1515	$14.90 (out of stock)
INDX Link Cable XT30	from $20.90
INDX Radial Part Cooling	$28.90
INDX Passive Tool (0.4 mm Standard Flow or Steel CHT)	$45.00 each
INDX CPAP Part Cooling	$89.90
Bondtech INDX Toolhead (Smart Head, Link Board, cabling)	$390.00 (available on backorder)

The development kit bundles the toolhead, Link Board, a crimp and connector kit and a Link Cable. Tools, docks and cooling are bought separately. Its store page says “Shipping starts end of October.”

Bondtech’s INDX page quotes passive tools at $40, while the store lists them at $45. The euro store shows the toolhead at €348.81 before VAT; the VAT-inclusive figure varies by country.

For the CORE One, Prusa announced conversion kits on April 23, 2026: $749 (4 tools) and $999 (8 tools) for the first batch, tariffs included. Euro prices were €669 and €899 including VAT. Prusa said kits would ship from June 2026, with the first batch out by the end of August. US reseller Swing Design listed an assembled CORE One+ (Gen 2) with INDX and 4 tools at $1,999 on October 14, 2026.

Team FDM’s roundup calls INDX “a version-one product” and reports that early units shipped with nozzles that “were not truly hardened.”

How is INDX different from StealthChanger?

StealthChanger swaps whole toolheads: each tool carries its own hotend, extruder, fans and OptoTap sensor on its own toolhead board. INDX keeps the extruder, electronics and induction coil on the moving head and parks only passive nozzles. An extra INDX tool lists at $45; an extra LDO StealthChanger tool-and-dock kit adds $59.90, without hotend or extruder.

	Bondtech INDX	StealthChanger
What stays on the gantry	Smart Head: extruder, motor, induction coil, IR temperature sensor, load cell, board	Shuttle on the X-rail carriage
What moves to the dock	A passive nozzle tool with no electronics	The whole toolhead: hotend, extruder, fans, OptoTap, toolhead board, mounted on a backplate
Wiring per tool	None	Heater, fans, extruder and OptoTap per tool; the docs recommend a toolhead board on each tool, on CAN or USB
Hotend choice	Bondtech passive tools only (0.25 mm to 1.0 mm nozzles)	Any hotend and extruder the chosen toolhead supports
Max nozzle temperature	300 °C	Set by the hotend you fit
Max tools	8 on a CORE One; set by dock space on the dev kit	4, 5 or 6 narrow tools on a 250, 300 or 350 mm Voron 2.4
Firmware	Prusa firmware on the CORE One; Kalico, Klipper (with indx_klipper) or RepRapFirmware on the dev kit	Klipper with klipper-toolchanger
Cost of one more tool	$45 tool, plus a $4.90 to $14.90 dock	$59.90 LDO tool-and-dock kit, plus hotend and extruder; Team FDM estimates $100 to $200 per tool for a DIY build

What the mechanical difference means when you buy and build:

• Moving mass. INDX moves the same head whatever tool it holds and adds only the passive tool. StealthChanger moves whichever complete toolhead is picked up, and each tool can use a different hotend, extruder or cooling setup.
• Heat-up. An INDX tool cools in its dock and is heated by the head’s coil after pickup, in 4 to 12 seconds. A StealthChanger tool has its own heater, wired through its own toolhead board.
• Probing. INDX probes with the load cell in the head. On StealthChanger the shuttle movement acts as a Tap probe, read by each tool’s OptoTap sensor.
• Cost math. The LDO price is the difference between the 1-tool ($246.70) and 2-tool ($306.60) West3D listings for a 300 mm Voron 2.4 on October 14, 2026. It covers a Nitehawk-36 toolboard, OptoTap, fans and dock parts. Hotend and extruder are extra.
• Which fits. If you need different hotends per tool or nozzle temperatures above INDX’s 300 °C limit, only StealthChanger allows that. If per-tool cost and wiring matter more, an extra INDX tool costs less and has no wiring of its own.

Build and setup guides for the alternative: StealthChanger and how to build a StealthChanger.