Wales produced a dominant final quarter to beat Trinidad & Tobago 72-64 at the Viola Arena in Cardiff on Sunday.
Helped by the shooting of Georgia Rowe and Eleanor Roberts, Wales opened up a four-point lead in the first quarter and maintained their advantage to lead 38-34 at half-time.
The World Cup-bound Calypso Girls dominated the third quarter, seizing on Wales errors to lead 56-53.
But a swarming Wales defence saw them dominate the last period 19-8.
Julie Hoornweg's side had also staged a thrilling recovery to beat Malawi 52-47 on Saturday, having trailed 15-9 after the first quarter.
The back-to-backs wins are a welcome boost after two heavy losses to South Africa.
World Cup-bound South Africa had beaten Wales 84-32 and 79-44 over two days in Cardiff.
Hoornweg's side now face two Tests against Grenada on 9 and 10 July.
Wales failed to qualify for the World Cup and is the first time that Wales have failed to reach the tournament.