Cov hmoov tshauv catcher no muaj peb daim, uas yog downstem, tais thiab 3 raj.Cov duab tshwj xeeb ntawm 3-tube yog ob qho tib si tshwj xeeb thiab tuaj yeem ntes cov plua plav zoo.Cov hmoov tshauv no tsuas muaj cov xim ntshiab xwb, tab sis nws tuaj yeem ua tau raws li koj cov kev xav tau ntawm kev yuav khoom vim tias nws cov yeeb nkab sib txuas tau teeb tsa ntawm 45 lossis 90 degrees thaum sib koom ua ke loj yog 14 hli lossis 18 hli, thiab qhov sib koom ua ke yog poj niam txiv neej.Koj tsuas yog yuav tsum xaiv qhov koj xav tau.Wb yuav tam sim no.