The ornamental design for a fastener for accessories, as shown and described.
1. Fastener for accessories
1.1 : Perspective
1.2 : Reference
1.3 : Reference
1.4 : Reference
1.5 : Perspective
1.6 : Front
1.7 : Top
1.8 : Left
1.9 : Right
1.10 : Perspective
1.11 : Front
1.12 : Top
1.13 : Back
1.14 : Left
1.15 : Right
The fastener for accessories is composed of a female part showing in the reproductions 1.10 to 1.15 and a male part showing in the reproductions 1.5 to 1.9; the bottom view of the female and male parts are omitted because they are a mirror image of the top view; the back view of the male part is omitted because it is a mirror image of the front view; The chain and the pendent shown in reproductions 1.2, 1.3 and 1.4 form no part of the claimed design.