GMGN Card Uses a Separate USDT Balance
The most important operating detail is simple: GMGN Card is funded before use. Launch posts and the tracked card record describe USDT top-up, no overdraft and a separate card balance.
A separate balance limits accidental spending
A separate balance limits accidental spending from assets you meant to keep. It also means a declined payment may just be a balance or fee-buffer problem rather than a wider account problem.
The network question is still open
The current card record lists USDT as the supported crypto, but the supported top-up blockchain networks are not clearly listed. That is worth checking inside the actual deposit screen before sending funds.
A better first transfer
Send enough for a small test purchase and fees, not a large operating balance. Once you know deposits, authorization holds, payments and refunds behave as expected, you can decide whether the convenience is worth more balance.
