427Pcs Technical Parts Cars Gears Axles - Wheels Connectors, Building Accessories Pieces Sets, MOC Technical Packs Bulksfor Technic Building Blocks Set(Compatible with Major Brands)

Good quality and good selection

This looks like a really nice set, but it was purchased primarily for the tred pieces, however there doesn't seem to be enough of a specific size to do 2 (e.g once in each side of a tank) and the quality on the larger treds is very poor, 4 broke in the first day. Solid pieces like the cogs and rods seem pretty study and the wheels are ok, although bit up to lego quality

Great quality spare parts

The quality of these parts are pretty decent, some very small differences in design compared to genuine Lego parts, but that does not affect the functionality of them. They are packaged in a box and split into 3 bags, so no complaints of packaging there. On close inspection other than very minor differences of connection points on a handful of the parts, they seem well made. No visual issues, the plastics seem very close to that of genuine parts. I do note however that the tank tracks look good, but some of them are slightly stiff on the joints, they do not freely flop as they should. This shouldn't be a problem though as they will likely loosen up in time and they are not so stiff that they don't move at all. These are a welcome addition to my collection of parts and will certainly be very useful for my custom builds.

My son is building lego engines and he needed some extra bits. He found them in this set and was really pleased.

It's a good range of moving parts, but you'll need to get a set of Technic beams or bricks to go along with it. The quality is variable though and some parts haven't been moulded cleanly, which can damage the other moving parts, including the genuine Lego parts you are combining these with. Some axles were warped and others hand poor moulding at the ends. The poor moulding of the track & chain links cause excessive friction to their motion. The price of the set is low enough that it's still worth having overall though. It would probably cost three times the amount, and much time, to order these pieces individually from the Lego website, but I wish Lego would sell such a set instead.