A curable adhesive precursor, comprising (a) a first part comprising: (i) a first epoxy curing agent comprising at least one polyether amine and having an amine equivalent weight of at least 55 grams per mole of amine equivalents; (ii) a second epoxy curing agent distinct from the first epoxy curing agent and/or a secondary curative; (iii) a metal salt catalyst; (iv) a toughening agent; (v) optionally, at least one phosphorous-based first flame retardant; (vi) optionally, at least one second flame retardant distinct from the at least one first flame retardant; and (b) a second part comprising: (i) a first epoxy resin in an amount in the range of from 20 to 45 wt.-%, based on the total weight of part; (ii) a second epoxy-based resin distinct from the first epoxy resin in an amount in the range of from 4 to 55 wt.-%, based on the total weight of part, wherein the second epoxy resin is selected from epoxy resins having a viscosity according to ASTM D 445 of less than 20 Pa·s, multifunctional epoxy resins and/or novolac epoxy resins; (iii) at least one phosphorous-based first flame retardant; (iv) optionally, at least one second flame-retardant distinct from the at least one first flame retardant; (v) an epoxy-based reactive diluent; (vi) a core-shell polymer toughening agent; and (vii) optionally, a filler material; wherein the total amount of flame retardant is lower than 50 wt.-% of the total curable adhesive precursor. (a) a first part comprising: (i) a first epoxy curing agent comprising at least one polyether amine and having an amine equivalent weight of at least 55 grams per mole of amine equivalents; (ii) a second epoxy curing agent distinct from the first epoxy curing agent and/or a secondary curative; (iii) a metal salt catalyst; (iv) a toughening agent; (v) optionally, at least one phosphorous-based first flame retardant; (vi) optionally, at least one second flame retardant distinct from the at least one first flame retardant; and (i) a first epoxy curing agent comprising at least one polyether amine and having an amine equivalent weight of at least 55 grams per mole of amine equivalents; (ii) a second epoxy curing agent distinct from the first epoxy curing agent and/or a secondary curative; (iii) a metal salt catalyst; (iv) a toughening agent; (v) optionally, at least one phosphorous-based first flame retardant; (vi) optionally, at least one second flame retardant distinct from the at least one first flame retardant; and (b) a second part comprising: (i) a first epoxy resin in an amount in the range of from 20 to 45 wt.-%, based on the total weight of part; (ii) a second epoxy-based resin distinct from the first epoxy resin in an amount in the range of from 4 to 55 wt.-%, based on the total weight of part, wherein the second epoxy resin is selected from epoxy resins having a viscosity according to ASTM D 445 of less than 20 Pa·s, multifunctional epoxy resins and/or novolac epoxy resins; (iii) at least one phosphorous-based first flame retardant; (iv) optionally, at least one second flame-retardant distinct from the at least one first flame retardant; (v) an epoxy-based reactive diluent; (vi) a core-shell polymer toughening agent; and (vii) optionally, a filler material; wherein the total amount of flame retardant is lower than 50 wt.-% of the total curable adhesive precursor. (i) a first epoxy resin in an amount in the range of from 20 to 45 wt.-%, based on the total weight of part; (ii) a second epoxy-based resin distinct from the first epoxy resin in an amount in the range of from 4 to 55 wt.-%, based on the total weight of part, wherein the second epoxy resin is selected from epoxy resins having a viscosity according to ASTM D 445 of less than 20 Pa·s, multifunctional epoxy resins and/or novolac epoxy resins; (iii) at least one phosphorous-based first flame retardant; (iv) optionally, at least one second flame-retardant distinct from the at least one first flame retardant; (v) an epoxy-based reactive diluent; (vi) a core-shell polymer toughening agent; and (vii) optionally, a filler material;