TESS stands for Tsuneishi Economical Standard Ship. The series consists of the TESS 40 (40,000DWT), TESS 45 (45,000DWT), and the newly developed TESS 52 (52,000DWT) types.

The first TESS 40 was completed for Ugland of Norway in 1984. The construction was followed by another 40 vessels of TESS 40 series in Japan. The first TESS 45 was constructed in 1994. This series was developed based on the TESS 40 type in answer to the requirements of the shipping market.

Increased DWT of the TESS 45 series is supported with the same capacity of ship speed and fuel consumption as achieved by the TESS 40 series. Mounting of three diesel generators and M0 conformity of the engine room are standard specifications for the series. The TESS design surpassed other similar bulkers with reduced specifications due to the inactive market at that time.

The new TESS 52 series has 18% more cargo space (67,500m³) over the TESS 45 (57,000m³).

The TESS series also includes EURO TESS 40, 45, and 52 with European specifications. The company intends to expand the market for the TESS series in the future.