#Measurement

Tools

5V, 9V, 12V or 24V? Choosing the Right DC UPS for a Router or Pet Camera, and What 'Without Battery' Means

A power cut takes down your router, your pet camera and the phone on the charger at the same time, which is exactly what a DC UPS is for: the box sits between the mains adapter and your device and switches to a battery the moment the mains drops. Before you order this one, settle the voltage. The listing offers the DC1018L in 5 V, 9 V, 12 V, 15 V and 24 V versions, and these are not interchangeable — feeding 24 V into a 12 V router destroys it, while 5 V will not even start a 12 V device. Read the label on the device's own power adapter and match that number exactly, not the figure printed on the router's casing. Next, the word that decides your total cost: 'Without Battery'. A battery is not included, and the listing does not say which type, how many cells or what capacity the compartment takes, so ask the seller before ordering — the backup time you get comes from the battery you fit, not from the UPS itself. Then check the current, not just the voltage: a router rated 12 V 1 A and one rated 12 V 2.5 A need different output capacity, and an undersized supply will simply shut down under load. Finally confirm two details the listing leaves open: the DC plug size, because a 5.5 x 2.1 mm barrel and a 5.5 x 2.5 mm one look identical and fit only one socket, and whether the unit passes mains power through to the device while charging the battery, with over-charge and over-discharge protection. 708 sold with a 98.0% positive rating.

Tools

Borescope Inspection Camera 4.3in IPS, 8mm Probe, 1080P, IP67 with 8 LEDs: Look Inside a Pipe or Engine Before You Take It Apart

A borescope answers one question that guessing never can: what is actually inside, and where. Before you cut a wall open, dig out a drain, or pull a cylinder head, the camera tells you whether you are looking at a blockage, a crack, corrosion, a lost part or nothing at all - and that changes the job from replacing everything to fixing one thing. This unit has a 4.3 inch IPS screen and its own 8mm probe with eight LEDs, 1080P resolution and an IP67 rating, so it works on its own without pairing with a phone. Check three things before buying. First, the probe diameter: 8mm needs a hole or pipe noticeably wider than itself to pass and to turn a corner, so measure the opening you intend to inspect - injector wells, thin air lines and small drain traps may simply not accept it. Second, working length: the listing does not state how long the insertion tube is, and a short cable cannot reach a blockage two metres down a pipe, so ask before ordering. Third, accessories: side-view mirrors, a hook, a magnet and a carry case are the difference between seeing a problem and retrieving it, and the listing does not confirm which are included. The IP67 rating applies to the probe, meaning it tolerates moisture and short immersion - it does not make the whole tool a dive camera.