One turn of a collar slackens or tightens adjustable buzzer bars, no screws, springs, milled flat edges & definitely no wobble! Ingenious engineering ensures maximum grip from the joint & all the bars are finished with the proven Pozi-Loc fittings for aligning alarms. They even self-adjust to prevent loosening in later life. Keep it tight, keep it screwless. Code: FC-SOL-POZI-BF Code: FC-SOL-POZI-BB