B2 is a medical based Paralympic classification for blind sport. Competitors in this classification Athletes in this classification have vision that falls between the B1 and B3 classes. The International Blind Sports Federation (IBSA) defines this classification as “visual acuity ranging from LogMAR 1.50 to 2.60 (inclusive) and/or visual field constricted to a diameter of less than 10 degrees.” It is used by a number of blind sports including para-alpine skiing, para-Nordic skiing, blind cricket, blind golf, five-a-side football, goalball and judo. Some sports have equivalents to this class, including adaptive rowing, athletics and swimming. Classification is often handled on the international level by IBSA though classification is also handled by national sport federations. There are exceptions for sports like athletics and cycling, where classification is handled by their own governing bodies. The B2 classification was first created by the IBSA in the 1970s, and has largely remained unchanged since despite an effort by the International Paralympic Committee (IPC) to move towards a more functional and evidence-based classification system. Some sports like athletics and swimming have independently created their own classification equivalent that is comparable to the IBSA created B1 class. Equipment utilized by competitors in this class may differ from sport to sport, and may include sighted guides, guide rails, beeping balls and clapsticks. There may be some modifications related to equipment and rules to specifically address needs of competitors in this class to allow them to compete in specific sports. Some sports such as athletics specifically do not allow a guide, whereas cycling and skiing require one.