Помогите, кто знает, что такое isotubes?

Контекст - газокаротажные работы. Вот например:
Contractor shall provide mud logging and early kick detection services including but not limited to, the provision of Personnel to execute the Service; the provision of fully automated, computerised system for measuring, monitoring, recording and transmitting the data; provision of certified mud logging unit, log quality control and processing lithology identification and description, sample collection, ISOTUBES and continuous gas and early kick detection, including the provision and operation of alarm system.

Или:
Purchasing of mud gas logging tools (isotubes and isotubes racks); record and send listing sampled isotubes at regular agreed time to Company and label and pack the isotubes and hand over to Company’s Site representative.

Заранее спасибо!