A degradation pick or holder shank for facilitating installation, retention and removal is disclosed. The shank may comprise an axially compressive portion that may contract radially when stretched axially and then expand again radially when released. An installation tool may be used to stretch the shank axially during insertion into a bore and then release the shank to retain it within the bore.

Aspects of the present disclosure relate to an apparatus including a drum rotatable about an axis of rotation and a support mount secured to the drum. The apparatus includes a support mount defining first and second fastener openings and first and second anchor openings. A replaceable holding block mounts to the support mount and the replaceable holding block has a front face and a rear face. The replaceable holding block defines a first fastener opening, a second fastener opening, and a tooth opening that extend through the replaceable holding block from the front face to the rear face. The first and second fastener openings of the replaceable holding block align with the first and second fastener openings of the support mount when the replaceable housing block is mounted to the block mounting surface. A tooth is secured to the replaceable holding block at the tooth opening.

A pick assembly is provided, comprising a bit assembly and a holder assembly; the bit assembly comprising a bit support body, a fastener mechanism and a deflectable member, cooperatively configured such the deflectable member can be deflected responsive to the progressive coupling of the bit support body to the fastener mechanism. The holder assembly comprises a holder body and is configured for accommodating and retaining the bit assembly by interference means. The holder assembly and bit assembly are cooperatively configured such that the retention of the bit assembly by the holder assembly by interference means can be progressively increased responsive to the progressive coupling of the bit support body with the fastener mechanism when the bit assembly is accommodated by the holder assembly, operative to prevent substantial movement of the bit support body relative to the holder body in use.