Dimensional Box

A box can be used to store items, as there is a limit to how many items the protagonist can carry at a time. There are a few physical boxes before Alphys upgrades the protagonist's phone in the Neutral and True Pacifist Routes. After the protagonist's phone is upgraded, two-dimensional boxes (one of which is the normal box) will appear in the phone list and can be used to move items around. The dimensional boxes can be accessed at any point in the game. If the protagonist is on a Genocide Route, Alphys does not show up to upgrade the protagonist's phone; however, three additional boxes are placed to compensate for this.

Each box can store up to 10 items, so in the Pacifist and Neutral Routes, the protagonist can be in possession of a total of 28 items while in the Genocide Route, the protagonist can have a total of 18 items.

The first time the protagonist opens a box (the first of which is located in Snowdin), it will contain a Tough Glove, which can be taken free of charge.

Box Locations
Snowdin Forest Snowdin Waterfall MTT Resort (Genocide Route) New Home (Genocide Route)
 * Located on the road just after Sans and Papyrus are met for the first time.
 * Located in front of the Snowed Inn and Shop.
 * Located on the left side of the falling rocks room, with a box hater's sign next to it.
 * Located next to the telescope prank Sans puts up.
 * Located outside of Gerson's shop.
 * Located in Temmie Village outside of Tem Shop.
 * Located at the bottom right corner of the lobby.
 * Located right outside the house, in front of the right window.
 * Located in Last Corridor, beside the save point.

Trivia

 * If the protagonist tries to use the dimensional boxes in Artifact Room the message "The box is aclog with the hair of a dog." will be displayed. The protagonist will not be able to use the boxes until they leave the room.

Dimensionale Box Пространственный сундук ‎Dimensional Box