Abstract: A probe comprises a first end that contacts and separates from a test object and a second end that contacts a circuit board to perform inspection of the test object. The second end is provided with a rotation restricted portion that restricts rotation of the probe about the axial direction thereof. An extendable portion, which is freely extendable and contractible in the axial direction of the probe and has at least one spiral slit, is provided between the first end and the second end. The second end is formed by a tubular member. Also, at least two of the extendable portions are provided between the first end and the second end, and an intermediate portion is formed between the extendable portions.

Abstract: An object of the present invention is to provide an electrical contactor highly resistant to deformation capable of achieving satisfactory performance of electrical contact with a small number of elements. An electrical contactor of this invention includes a barrel having a spring part achieving a spring function formed in a partial section, and a first plunger and a second plunger inserted in the barrel through an opening at one end and an opening at an opposite end of the barrel and fixed to the barrel. It is preferable that an end part of the first plunger in the barrel and an end part of the second plunger in the barrel are placed in internal space of the same non-spring part not to achieve a spring function. It is preferable that the barrel has three or more spring parts separated while non-spring parts are placed between the spring parts.

Abstract: A probe comprises a first end that contacts and separates from a test object and a second end that contacts a circuit board to perform inspection of the test object. The second end is provided with a rotation restricted portion that restricts rotation of the probe about the axial direction thereof. An extendable portion, which is freely extendable and contractible in the axial direction of the probe and has at least one spiral slit, is provided between the first end and the second end. The second end is formed by a tubular member. Also, at least two of the extendable portions are provided between the first end and the second end, and an intermediate portion is formed between the extendable portions.

Abstract: An object of the present invention is to provide an electrical contactor highly resistant to deformation capable of achieving satisfactory performance of electrical contact with a small number of elements. An electrical contactor of this invention includes a barrel having a spring part achieving a spring function formed in a partial section, and a first plunger and a second plunger inserted in the barrel through an opening at one end and an opening at an opposite end of the barrel and fixed to the barrel. It is preferable that an end part of the first plunger in the barrel and an end part of the second plunger in the barrel are placed in internal space of the same non-spring part not to achieve a spring function. It is preferable that the barrel has three or more spring parts separated while non-spring parts are placed between the spring parts.

Abstract: A transglutaminase catalyzing an acyl transfer reaction of a .gamma.-carboxyamide group of a glutamine residue in a peptide or protein chain in the absence of Ca.sup.2+.