The Ferris-Smith Sewall Orbit Retractor (9x51mm, No Slot) is a surgical instrument primarily used in ocular or orbital surgeries. The 9x51mm size refers to the dimensions of the retractor blade, with the size ensuring it provides adequate reach and coverage for working within the orbital area. The no slot design means the retractor has a solid blade without a slot for hook attachment, providing a secure grip for manipulating the orbital tissue and keeping the eyelid or surrounding structures retracted during surgery.