Abstract: Knives configured to use interchangeable blades, blades for those knives, and methods of making an using the knives and blades are disclosed. One knife includes a latch assembly that retains a blade in a slot of the latch assembly using a dual-stage locking mechanism wherein two different latches must be operated to exchange the blade in the slot. One latch is a button that translates a pin through the slot, and the other latch is a rocker lever that rotates into and out of contact with a notch, recess, or groove in the blade. The first latch controls movement of the second latch in order to help avoid inadvertent removal or dislodgement of the blade. Some blades include multiple notches or recesses so that they provide multiple points of contact that resist translation and rotation of the blade out of the slot, even when subjected to unusually-directed forces.

Abstract: According to one representative embodiment, a knife includes a handle having a forward end portion and a rear end portion, and a blade coupled to the forward end portion of the handle. The handle includes first and second opposing side portions, the first side portion including a cutting member at the rear end portion of the handle and the second side portion including an extension portion at the rear end portion of the handle. The extension portion extends rearwardly past the cutting member in the direction of the length of the handle. The cutting member and the extension portion are spaced apart from each other a distance sufficient to receive the side wall of the lid of a tobacco can.

Abstract: According to one representative embodiment, a knife comprises a handle having a forward end portion and a rear end portion, and a blade coupled to the forward end portion of the handle. The handle comprises first and second opposing side portions, the first side portion comprising a cutting member at the rear end portion of the handle and the second side portion comprising an extension portion at the rear end portion of the handle. The extension portion extends rearwardly past the cutting member in the direction of the length of the handle. The cutting member and the extension portion are spaced apart from each other a distance sufficient to receive the side wall of the lid of a tobacco can.

Abstract: A water bottle includes a bottle body, a cap and a base. The bottle body includes a wall structure extending from a bottom end to a top end. The top end includes an opening. An outer surface of the wall structure may include a plurality of finger grip recesses and at least one thumb grip recess. The cap is configured to releasably connect to the top end of the bottle body to close the opening with a fluid-tight seal. The cap has a pointed portion that provides at least one top pressure point. The base is positioned at the bottom end of the bottle body and includes at least one pointed portion that provides at least one bottom pressure point. The at least one top and at least one bottom pressure points provide self-defense features for the water bottle.

Abstract: A lifting mechanism or locking mechanism includes a housing, an axle attached to the housing, and an element including a cam surface mounted for rotation on the axle. The distance between the cam surface and the housing changes between a maximum clearance distance and a minimum clearance distance as the element rotates about the axle. The lifting mechanism also includes a line which can be moved between a first position over the cam surface and a second position.

Abstract: A lifting mechanism or locking mechanism includes a housing, an axle attached to the housing, and an element including a cam surface mounted for rotation on the axle. The distance between the cam surface and the housing changes between a maximum clearance distance and a minimum clearance distance as the element rotates about the axle. The lifting mechanism also includes a line which can be moved between a first position over the cam surface and a second position.