Abstract: A leash has a first end for gripping and a second end for securing to an animal, a length of elastic material, and a length of inelastic material including first and second portions. The length of elastic material and length of inelastic material are configured so that application of tensile force to the first or second end of the leash extends the length of elastic material. Extension of the length of elastic material causes the first portion of the length of inelastic material to lengthen and the second portion of the length of inelastic material to correspondingly shorten. Contraction of the length of elastic material causes the second portion of the length of inelastic material to lengthen and the first portion of the inelastic material to correspondingly shorten, preventing slack in the leash upon sudden deapplication of a tensile force.

Abstract: An exercise device includes an elastic member having a first hand portion and a band portion. The first hand portion includes a first finger sheath portion and a second finger sheath portion. The band portion extends from the first hand portion. The band portion has a generally rectangular flat sheet shape. The finger sheath portions of the first hand portion are aligned along a first plane. Preferably, the first plane is substantially perpendicular to a surface plane of the band portion, such that openings for the finger sheath portions of the first hand portion are formed in the surface plane of the band portion. The exercise device preferably consists of a single molded piece, wherein the single molded piece is the elastic member. The exercise device preferably includes a second hand portion like the first hand portion (preferably mirror symmetrical), with the band portion extending there between.