I just called them, they are located between KFC and Hardees, Salwa road, take service rd

INSTROL LLC,
P. O. Box 31483,
Doha, Qatar
Tel. 44419968;
Fax 44419969

SUPPLY, INSTALLATION, CALIBRATION, COMMISSIONING & MAINTENANCE OF FIRE & GAS DETECTION AND PROTECTION SYSTEMS, GAS/MOISTURE ANALYSER PACKAGES, ENVIRONMENTAL MONITORING SERVICES, EXPLOSION PROOF EQUIPMENTS, NAVAIDS, SAFETY EQUIPMENT, B.A/AIR LOOP CASCADE SYSTEMS