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instrument
control room  >     OUTDOORS
        MUSICAL SLAP TUBES SCRAPERS INTERLOCKING RAINSTICKS WHIRLERS SLAPDRUMS Aluminium :tubes,gongsetc. all are fine outside, so I’ll just mention the others......
Whirlers - you spin
them round ( they’ve got ballbearings inside)
Slaptubes- you hit
over the end different lengths of pipe
Slapdrums- thwack the whole thing
Rainsticks- also filled with ballbearings & joined with straps (move one & they all move)
Scrapers- are grooved 
industrial pipe