Is designed for supporting the natural or artificial roof of the longwalls with coal faces length between 80- 120 m in the overage coal seams.
The powered roof support can operate together with the armoured face conveyor and the longwall shearer forming the so called mechanized complex.

The powered roof suppoting sections type SMA-1 can be grouped three together, connected one to amother by means of common crossbar, forming the operational system called Troika.

Technical characteristics	MU	SMA-1
Type of the support	-	two leg shield
Working height Hmin/Hmax	mm	2500/3500
Inter axis step	mm	1480
Advancing step	mm	630/800
No. of props - props lifting power	kN	2x1400
Floor pressure	kN/m2	426
Operation angle - on advancing direction - on declivity	grd	± 10 max. 35 left and right
Operation reagent	-	oil + water (3-5 %) emulsion
Weight	kg	10300