bead 16 39 terminate at corner 17 39 depending from arm 18 is an l shaped member 19 comprising a substantially flat first leg 20 and a substantially flat second leg 21 set at a right angle to leg 20 in utilizing the fastener 10 the legs of the stud member are pressed into an insulation member not shown adjacent an edge thereof and spaced from that edge a distance equal to the length of arm 18 the leg 20 thus extends along the side of the insulation member and is closely adjacent thereto the length of the leg 20 is substantially equal to the width of the side of the insulation such that the second leg 21 is essentially coplanar with the 34 back 34 of the insulation the second leg 21 and the back surface of the insulation member are placed against a supporting structure and leg 21 is attached by suitable means to the supporting structure the fastener and insulation member are thus secured to the supporting structure suitable means for attaching leg 21 to the supporting structure include pins nails screws rivets and the like which are driven through the leg and into the supporting structure the length and width of leg 21 are not critical except that they should be sufficient to permit the use of desired means of driving the pin nail etc such as for example a pneumatic or powder actuated hammer fastener 10 is illustrated.