<P> A roach is the remains of a joint, blunt or roll up cigarette after most of it has been smoked . </P> <P> In Europe, the United Kingdom and most Commonwealth nations, the term is often used more specifically to refer to a short tube, commonly torn from a pack of rolling papers, that may be present in the unlit end of a joint . This hollow mouthpiece, customarily made of thin cardboard, is termed a filter in North America . In other parts of the world other materials are also used, e.g. steel . The steel roach was invented to fill the gap of reusable product category and it also does not have as much crystal deposits like paper filters . It is commonly set in position during the rolling process, or may be inserted later . When the use of a roach is employed, a joint can still be held securely after it has burnt down to a short length; thus, the entire length of the joint may be smoked, without the aid of a roach clip . </P> <P> In Spanish, tabaco de cucaracha ("roach tobacco") refers to powdery, low - quality tobacco . </P>

Why do you need roach for a joint
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