Check the listing for details. On-Stage MSA9800 Telescoping Dual-microphone Boom Arm. Condition: New. Listed at 41.95 USD. A More Versatile Boom Arm One mic or two — the On-Stage MSA9800 telescoping mic boom accommodates either, expanding the capabilities of any standard mic stand. Eliminating the need for a second mic stand, the MSA9800 is an indispensable asset for many Sweetwater recording engineers; its counterweight can support your heavier mics, or you can remove it to accommodate a second microphone on your existing stand. This capable boom arm accepts any standard mic clip on both ends and can be adjusted from 21.5 to 36 inches. Equip the MSA9800 for your live show and mic up larger speaker cabs, or keep it in the studio and enjoy the added stability for those large-diaphragm condensers.