The WhiteSpace, a Thailand MVNO operating under the Penguin brand, reached a deal to expand its capacity using state-owned operator TOT’s 2.1GHz spectrum.

Penguin, which launched 3G service in April 2016 and claims 300,000 active users, already uses CAT Telecom’s 850MHz network to provide low-cost prepaid service. It plans to enable customers on the 2.1GHz network to roam on CAT’s network by early 2018, Bangkok Post reported.

The MNVO today sells about 40,000 SIM cards a month and aims to double its active user base in the next 12 months, The WhiteSpace CEO Chaiyod Chirabowornkul said.

Chaiyod told Bangkok Post he isn’t concerned by the launch of Line Mobile, an independent unit owned by a subsidiary of third-ranked dtac which uses the latter’s network, because its target group is different.

Penguin is focused on prepaid customers, primarily outside of major cities, he said. In addition, while Line Mobile is targeting digitally focused consumers with online support, he doesn’t believe the model will work in rural areas, Bangkok Post said.

Two other MVNOs use TOT’s 2.1GHz network – i-Kool and Buzzme. TOT also runs its own 3G service on the 2.1GHz band.