A checker nut for locking a threaded body to a threaded rod includes a main body portion having a bearing surface for engaging a threaded body; the main body portion including a central opening with an inside surface; and a single female thread disposed on the inside surface and extending therefrom, the female thread for cooperating with threads on a threaded rod.

An insert nut includes a cylindrical portion into which a bolt is removably insertable. An inner periphery of the cylindrical portion includes a first region, a second region and a third region which are provided in the order named from an upstream side to a downstream side with respect to an insertion direction of the bolt at an inner periphery thereof. The first region and the third region include a female screw portion threadably engageable with the bolt. The second region has a minimum inner diameter larger than D1+2h10.3, where D1 is an inner diameter of the female screw portion in the first region at a screw thread position and h1 is a height of a screw thread of the female screw portion in the first region.

An anti-disassembly connector, including: a connecting portion; and at least two bosses, where the bosses protrude from an end or a peripheral wall of the connecting portion, the bosses extend along a circumferential edge of the connecting portion, each of the bosses has a force-bearing surface and a force-releasing surface that are disposed opposite to each other, and two bosses are disposed at intervals along the circumferential edge of the connecting portion or the peripheral wall of the connecting portion; and a force-bearing sideline is formed on a side of the force-bearing surface away from the connecting portion, a distance between force-bearing sidelines of the two bosses is clamping distance L, an outer diameter of each of the at least two bosses has D, and L<D.

A functional element having a functional portion, a generally tubular rivet portion and a ring-like sheet metal contact surface is characterised in that features of shape are provided at the rivet portion for co-movement of the sheet metal part during the formation of the rivet bead, in particular at the free end of the rivet portion and/or at the radially outer side of the rivet portion, at least in the region adjacent the free end of the rivet portion. A component assembly comprising a functional element and a sheet metal part as well as a method for the attachment of a functional element to the sheet metal part are also claimed.

A functional element having a functional portion, a generally tubular rivet portion and a ring-like sheet metal contact surface is characterised in that features of shape are provided at the rivet portion for co-movement of the sheet metal part during the formation of the rivet bead, in particular at the free end of the rivet portion and/or at the radially outer side of the rivet portion, at least in the region adjacent the free end of the rivet portion. A component assembly comprising a functional element and a sheet metal part as well as a method for the attachment of a functional element to the sheet metal part are also claimed.

Disclosed herein is an integrated bonding mid clamp device for solar panel mounting and grounding, as well as a related system and method. The integrated bonding mid clamp includes a deformable toothed washer for breaking an anodized layer of a solar panel frame. The deformable toothed washer is capable of deforming to avoid obstructing proper contact between the mid clamp and the solar panel frame.

A fastener includes an elongated shaft having a first end, a second end, and a shaft body, a head portion, and a threaded portion. At least one inner feed channel extends through the head portion and the shaft body and terminates proximal to the threaded portion. The fastener has a plurality of flutes formed along and circumferentially spaced around an outer surface of the shaft body and an outer surface of the head portion. Each flute has a first end and extends from a first location proximal to the threaded portion, along the outer surface of the shaft body, and radially outward along the outer surface of the head portion. The fastener further has one or more lateral feed channels formed laterally through the shaft body and connecting the inner feed channel to at least two opposing flutes on the outer surface of the shaft body.

An object holding structure includes: an inner member including an end surface, a first clamping surface located radially outward of the end surface, and hook portions arranged in a circumferential direction at intervals on the end surface; an outer member located radially outward of the inner member, including an end surface and a second clamping surface opposed to the first clamping surface through an object; a key plate contactable to the end surface and the end surface; and a retaining ring held between the key plate and claw portions of the hook portions. The key plate includes a first ring facing the end surface, a second ring provided radially inward of the hook portions, and inner tabs located between the hook portions and linking the first ring and the second ring.

A retention nut includes a fastening portion and a mating portion. The fastening portion has internal threads. The mating portion is connected to the fastening portion and includes a snap wing.

A retention nut includes a fastening portion and a mating portion. The fastening portion has internal threads. The mating portion is connected to the fastening portion and includes a snap wing.