Mosquito Coils, Brand Name : Hang xanh

A mosquito coil is a mosquito repelling incense, usually shaped into a spiral, and typically made from a dried paste of pyrethrum powder. The coil is usually held at the center of the spiral, suspending it in the air, or wedged by two pieces of fireproof nettings to allow continuous smoldering. Burning usually begins at the outer end of the spiral and progresses slowly toward the centre of the spiral, producing a mosquito-repellent smoke. A typical mosquito coil can measure around 15 cm in diameter and lasts around 8 hours. Mosquito coils are widely used in Asia, Africa, and South America.
Active ingredients found in mosquito coils may include:
Pyrethrum - a natural, powdered material from a kind of chrysanthemum plant; performance moderate
Pyrethrins - an extract of the insecticidal chemicals in pyrethrum
Allethrin - sometimes d-trans-allethrin, the first synthetic pyrethroid
Esbiothrin - a form of allethrin
Butylated hydroxytoluene (BHT) - an optional additive to prevent pyrethroid from oxidizing during burning
Piperonyl butoxide (PBO) - an optional additive to improve the effectiveness of pyrethroid
N-Octyl bicycloheptene dicarboximide (MGK 264) - an optional additive to improve the effectiveness of a pyrethroid