The Gator Case G-SUB 2224-25 Rolling Sub-Woofer Speaker Bag is a nylon slip-on bag with caster board made to transport a powered sub-woofer speaker. It has two protective skid bars and two external pockets for cables and accessories. The bag is transported by an adjustable, removable nylon strap, tow handle, four reinforced lift handles, two webbed nylon handles to assist placing case onto sub woofer and a built-in caster plate with four wheels, of which two are fixed for control while transporting.