Adjustable sleeping bag

A sleeping bag comprising:

• an insulated tubular member open at a first longitudinal end associated with a user's head and closed at a second longitudinal end associated with the user's feet, wherein the insulated tubular member comprises a bottom side configured to lay below the user, and wherein the insulated tubular member comprises a top side configured to lay above the user;
• a first material comprising an outer shell of the tubular member;
• a second material comprising an inner liner of the tubular member;
• insulation material enclosed by the outer shell and the inner liner;
• an expansion panel positioned on the top side of the insulated tubular member, further comprising:
• a first end positioned nearest the first longitudinal end of the insulated tubular member and comprising a first width;
• a second end positioned nearest the second longitudinal end of the insulated tubular member and comprising a second width greater than the first width;
• a plurality of baffled chambers running circumferentially around the insulated tubular member, wherein at least one of the plurality of baffled chambers passes through the expansion panel:
• a zipper, further comprising:
• a first portion attached to a first side of the expansion panel and running longitudinally along the top side of the insulated tubular member;
• a second portion attached to a second side of the expansion panel and running longitudinally along the top side of the insulated tubular member;
• and
• a zipper slider removably attached to at least one of the first portion and the second portion, wherein the zipper slider is configured to zip the first portion and the second portion together to close the expansion panel, and wherein the zipper slider is configured to unzip the first portion and the second portion to open the expansion panel.