A wearable medical device may be unpacked, prepared, and/or used while being grasped with a single hand position. For example, the device may be removed from a package, primed, and/or adhered to the skin of a user while being grasped with the single hand position. Optionally, the device may be used with a single hand. Optionally, the device includes a delivery interface (for example, including a needle tip and/or a skin contact surface). Optionally, the device includes a protector that preserves sterility of the delivery interface. Optionally, the cover can be removed with a single hand. Optionally, removal of the cover is performed with the same hand position as placement of the device on a delivery site.
