A derivative of a GLP-1 analogue, which analogue comprises a first K residue at a position corresponding to position 27 of GLP-1 (SEQ ID NO: 1); a second K residue at a position corresponding to position 36 of GLP-1; and a maximum of ten amino acid changes as compared to GLP-1; wherein the first K residue is designated K 27, and the second K residue is designated K 36; wherein the analogue comprises a GLP-1 analogue of Formula I: Formula I: wherein Xaa 7 is L-histidine, imidazopropionyl, α-hydroxy-histidine, D-histidine, desamino-histidine, 2-amino-histidine, β-hydroxy-histidine, homohistidine, N α -acetyl-histidine, N α -formyl-histidine, α-fluoromethyl-histidine, α-methyl-histidine, 3-pyridylalanine, 2-pyridylalanine or 4-pyridylalanine; Xaa 8 is Ala, Gly, Val, Leu, Ile, Thr, Ser, Lys, Aib, (1-aminocyclopropyl) carboxylic acid, (1-aminocyclobutyl) carboxylic acid, (1-aminocyclopentyl) carboxylic acid, (1-aminocyclohexyl) carboxylic acid, (1-aminocycloheptyl) carboxylic acid, or (1-aminocyclooctyl) carboxylic acid; Xaa 12 is Lys or Phe; Xaa 16 is Val or Leu; Xaa 18 is Ser, Arg, Asn, Gln, or Glu; Xaa 19 is Tyr or Gln; Xaa 20 is Leu, Lys, or Met; Xaa 22 is Gly, Glu, Lys, or Aib; Xaa 23 is Gln, Glu, or Arg; Xaa 24 is Ala or Lys; Xaa 25 is Ala or Val; Xaa 31 is Trp or His; Xaa 34 is Glu, Asn, Gly, Gln, or Arg; Xaa 37 is Gly, Ala, Glu, Pro, Lys, Arg, or absent; Xaa 38 is Ser, Gly, Ala, Glu, Gln, Pro, Arg, or absent; and Xaa 39 is Gly or absent; which derivative comprises two protracting moieties attached to K 27 and K 36, respectively, via a linker, wherein the protracting moiety is selected from Chem. 2 and Chem. 1: Chem. 2: HOOC-C 6 H 4 -O-(CH 2) y -CO-* Chem. 1: HOOC-(CH 2) x -CO-*, in which x is an integer in the range of 6-16, and y is an integer in the range of 3-17; and the linker comprises Chem. 5: wherein k is an integer in the range of 1-5, and n is an integer in the range of 1-5; or a pharmaceutically acceptable salt, amide, or ester thereof. Formula I: wherein Xaa 7 is L-histidine, imidazopropionyl, α-hydroxy-histidine, D-histidine, desamino-histidine, 2-amino-histidine, β-hydroxy-histidine, homohistidine, N α -acetyl-histidine, N α -formyl-histidine, α-fluoromethyl-histidine, α-methyl-histidine, 3-pyridylalanine, 2-pyridylalanine or 4-pyridylalanine; Xaa 8 is Ala, Gly, Val, Leu, Ile, Thr, Ser, Lys, Aib, (1-aminocyclopropyl) carboxylic acid, (1-aminocyclobutyl) carboxylic acid, (1-aminocyclopentyl) carboxylic acid, (1-aminocyclohexyl) carboxylic acid, (1-aminocycloheptyl) carboxylic acid, or (1-aminocyclooctyl) carboxylic acid; Xaa 12 is Lys or Phe; Xaa 16 is Val or Leu; Xaa 18 is Ser, Arg, Asn, Gln, or Glu; Xaa 19 is Tyr or Gln; Xaa 20 is Leu, Lys, or Met; Xaa 22 is Gly, Glu, Lys, or Aib; Xaa 23 is Gln, Glu, or Arg; Xaa 24 is Ala or Lys; Xaa 25 is Ala or Val; Xaa 31 is Trp or His; Xaa 34 is Glu, Asn, Gly, Gln, or Arg; Xaa 37 is Gly, Ala, Glu, Pro, Lys, Arg, or absent; Xaa 38 is Ser, Gly, Ala, Glu, Gln, Pro, Arg, or absent; and Xaa 39 is Gly or absent; Xaa 7 is L-histidine, imidazopropionyl, α-hydroxy-histidine, D-histidine, desamino-histidine, 2-amino-histidine, β-hydroxy-histidine, homohistidine, N α -acetyl-histidine, N α -formyl-histidine, α-fluoromethyl-histidine, α-methyl-histidine, 3-pyridylalanine, 2-pyridylalanine or 4-pyridylalanine; Xaa 8 is Ala, Gly, Val, Leu, Ile, Thr, Ser, Lys, Aib, (1-aminocyclopropyl) carboxylic acid, (1-aminocyclobutyl) carboxylic acid, (1-aminocyclopentyl) carboxylic acid, (1-aminocyclohexyl) carboxylic acid, (1-aminocycloheptyl) carboxylic acid, or (1-aminocyclooctyl) carboxylic acid; Xaa 12 is Lys or Phe; Xaa 16 is Val or Leu; Xaa 18 is Ser, Arg, Asn, Gln, or Glu; Xaa 19 is Tyr or Gln; Xaa 20 is Leu, Lys, or Met; Xaa 22 is Gly, Glu, Lys, or Aib; Xaa 23 is Gln, Glu, or Arg; Xaa 24 is Ala or Lys; Xaa 25 is Ala or Val; Xaa 31 is Trp or His; Xaa 34 is Glu, Asn, Gly, Gln, or Arg; Xaa 37 is Gly, Ala, Glu, Pro, Lys, Arg, or absent; Xaa 38 is Ser, Gly, Ala, Glu, Gln, Pro, Arg, or absent; and Xaa 39 is Gly or absent;