Abstract: A compass cutter has a main body fastened with an extension rod which is connected with a slidable seat slidable along the extension rod. The main body is further provided with a locating block, a protective cover, a blade, a fixation block, and an insertion pin. The slidable seat is provided with a locating block, a connection rod, a locating pin, and a shield. The compass cutter can be expanded, through the movement of the extension rod. The locating pin and the blade are covered by the shield to protect the user of the compass cutter.

Abstract: A modular container is formed of a casing, a seat ring, a rotary cover, and a base. The casing is provided with a plurality of retaining holes and retaining projections. The seat ring is located in the top of a cylindrical object which is formed by the casing. The base if disposed at the bottom of the cylindrical object. The rotary cover is provided with a plurality of retaining protrusions. The seat ring is provided with a plurality of locating slots. The rotary cover is located by the seat ring such that the retaining protrusions of the rotary cover are located in the locating slots of the seat ring.

Abstract: A compass cutter comprises a main body fastened with an extension rod which is connected with a slidable seat slidable along the extension rod. The main body is further provided with a locating block, a protective cover, a blade, a fixation block, and an insertion pin. The slidable seat is provided with a locating block, a connection rod, a locating pin, and a shield. The compass cutter can be expanded, thanks to the extension rod. The locating pin and the blade are shield by the shield to protect the user of the compass cutter.

Abstract: A modular container is formed of a casing, a seat ring, a rotary cover, and a base. The casing is provided with a plurality of retaining holes and retaining projections. The seat ring is located in the top of a cylindrical object which is formed by the casing. The base if disposed at the bottom of the cylindrical object. The rotary cover is provided with a plurality of retaining protrusions. The seat ring is provided with a plurality of locating slots. The rotary cover is located by the seat ring such that the retaining protrusions of the rotary cover are located in the locating slots of the seat ring.

Abstract: A round knife including a handle which is provided in a head end thereof with a slot for receiving pivotally a round knife blade and a support frame. The slot is provided with a protective groove for retaining and locating the support frame. When the support frame is securely engaged with the protective groove, the round knife blade is concealed securely by a protective shield of the support frame. The support frame can be actuated by an actuation piece to rotate so as to expose the round knife blade to execute the cutting operation.