<prompt> Abrasion collar is seen in:Gunshot injuryStab woundDrowningRailway track accident  <response>: Abrasion collarring: Proof of bullet entry wound. Due to spinning motion of bullet. Impoance: Round Abrasion collar - if the bullet hits at right angle to the skin surface. Oval abrasion collar - if the bullet hits at oblique angle to the skin surface Diameter of the entry wound abrasion collar gives the approximate diameter of the bullet. Grease collar bullet wipe: A blackgray colored ring is seen lining the entrance wound. Due to the deposition of lubricants, gun oil or lead from the bullet. 