This router is a re-branded and re-flashed Rosewill RNX-N300RT. The Rosewill RNX-N300RT uses the same board found in the TL-WR841N[D] v8.x. The stock RNX-N300RT ships with DRM and CAN NOT be flashed without non-free software (unless you have a chip clip and SPI flasher). Some versions (v1) requires the flash chip to be removed before an SPI programmer can be used. ThinkPenguin's offering ships with libreCMC, does not ship with DRM and can be fully re-programmed.
The names of the firmware images for this device are librecmc-ar71xx-generic-tl-wr841-v8-squashfs-*
See our flavors page for a description of each type of libreCMC image.