why do you need roach for a joint
Roach (smoking) 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.[citation needed] 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.[1]
Antenna (biology) Antennae are connected to the first one or two segments of the arthropod head. They vary widely in form, but are always made of one or more jointed segments. While they are typically sensory organs, the exact nature of what they sense and how they sense it is not the same in all groups. Functions may variously include sensing touch, air motion, heat, vibration (sound), and especially smell or taste.[1][2] Antennae are sometimes modified for other purposes, such as mating, brooding, swimming, and even anchoring the arthropod to a substrate.[2] Larval arthropods have antennae that differ from those of the adult. Many crustaceans, for example, have free-swimming larval forms that use their antennae for swimming.