The invention relates to a derivative of a GLP-1 analogue, which analogue comprises a first K residue at a position corresponding to position 37 of GLP-1(7-37) (SEQ ID NO: 1), a second K residue at a position corresponding to position 26 of GLP-1(7-37), and a maximum of ten amino acid modifications as compared to GLP-1(7-37), wherein the first K residue is designated K37, and the second K residue is designated K26, which derivative comprises two albumin binding moieties attached to K26 and K37, respectively, wherein the albumin binding moiety comprises a protracting moiety selected from:Chem. 1, Chem. 2, Chem. 3 or Chem. 4; or a pharmaceutically acceptable salt, amide, or ester thereof.