DAC are listed in this section because the manufacturer states that it is a 16 bit DAC or the manufacturer is completely unclear about bit depth and sample rate supported so it probably is 16 bits/ 48kHz.
Today you can buy a 24 bit USB DAC at an affordable price.
No reason to limit you to 16 bit anymore.
The information below is as supplied by the manufacturers website.
USB: 32kHz, 44.1kHz, 48kHz
Vintage Computer Audio: SilverStone EB01B - Michael Lavorgna
Texas Instruments PCM1744
USB: 16 bits/48 kHz
MusicStreamer+ $249.95
TI DAC PCM1794
USB: 16 bits/48 kHz
192 kHz Upsampling DAC / Headphone Amp with USB and S/PDIF inputs.
Beresford
TC-7520 £149.99
Inputs: USB/COAX/TOSLINK SPDIF: 24bit/96kHz
USB: 16/48
Seperate re-clocking circuits for USB and SPDIF
Output: line, class A head- and pre-amp.
A lot of information can be found on The Art of Sound Forum

USB: 16-bit / 32, 44.1, 48 kHz
DAC: non-oversampling (NOS). Audio playback occurs at the recorded frequency (), with no resampling, upsampling, or oversampling.
Output: RCA
32 bit Texas Instruments Digital Signal Processor (DSP)
DAC: Twin Wolfson WM8740
Digital input:
2x S/PDIF (coax & Toslink)USB input connects direct to PC without drivers
| Digital input word widths supported: | 16 -24bit (16 bit for USB) |
| Digital input sampling frequencies supported: | 32kHz, 44.1kHz, 48kHz, 88.2kHz, 96kHz. |
| USB input | 16 bits / 44.1,48kHz |
| Audio output up-sampling: | Fixed 24bit/192kHz |
Output
Analog: RCA/XLR
Digital: 1x S/PDIF (coax & /Toslink)
How the adaptive mode USB of this DAC performs compared with asynchronous USB can be found here.
Digital input
Sampling rate: 44kHz – 96kHz
Analog output: RCA
Digital input
DAC
Analog output:
Class A discrete FET based output stage
Balanced (XLR) and unbalanced (RCA)
Upsampling: 24 bit/192 kHz
Fully balanced design
Digital input:
Dual Mono DAC (2 x Burr Brown PCM1796)
USB-Codec: Texas-Instruments PCM2906 Transceiver
Analog output:
Single ended Class A amplifiers
balanced (XLR) and unbalanced (RCA)
Digital output: COAX, TOS, AES/EBU-Input are routed to the USB-output (up to 48kHz/16bit).
Digital input: USB, Optical, Coaxial, AES/EBU(XLR)
Analog output: balanced (XLR) and unbalanced (RCA)
32, 44.1, 48, 88.2, 96, 176, 192K sampling
Digital input:
USB (1), COAX (2), OPTICAL (2),AES-EBU (1) BNC (2)
Sample rates: 16-24Bit PCM, 16Bit 32K-48K USB
Analog output: balanced (XLR) and unbalanced (RCA)

Digital input (5): AES/EBU (XLR), S/PDIF (BNC, RCA, TosLink), USB.
Sample rates: 32–96kHz (S/PDIF, AES/EBU), 32kHz–48kHz (USB).
Analog output: RCA (1 pair), balanced XLR (1 pair).
Digital input: Asynchronous USB
No oversampling and no analog or digital filter
16bit @ 44.1kHz WAV/ FLAC only
Analog output: RCA (1 pair)
Digital input:
2 x SP/DIF BNC Coax
2 x AES Balanced XLR Input
2 x Plastic fibre optic ( TOSlink )
1 x USB ( B type )
1 x Bluetooth supporting A2DP Stereo Audio
Sample frequencies 32kHz – 96kHz Single Cable,
176kHz & 192kHz Dual Cable ( Dual data mode )
Random master clock jitter of less than 3pS cycle to cycle
Analog output: 2 X RCA /
2 X balanced (XLR)