Did you know? Andreas Stihl patented the first electric chainsaw in 1926 and the first petrol chainsaw in 1929 — earning the title Father of the Chainsaw.
Did you know? Johan Petter Johansson invented the modern adjustable wrench (spanner) in 1892 while working at Bahco — the tool used by every tradesperson today.
Did you know? A British company that manufactures router cutters, saw blades, and the famous AirShield Pro — one of the first powered respirators for woodworkers.
Did you know? Invented the first portable circular saw in 1927 and pioneered the dust extraction system that is now standard in professional workshops.
Did you know? Started by making carbon-filament lamps. The Philips head screw was NOT invented by Philips — it was invented by Henry F. Phillips, a completely different person.
Did you know? One of the oldest British chemical manufacturers, originally producing turpentine substitute. Their wood preservers have protected UK homes for over 145 years.
Did you know? The name comes from "Cuprum" (Latin for copper) and "Naphthol" — copper naphthenate was the original wood preservative formula invented in 1911.
Did you know? British General (BG) has been the UK's go-to brand for electrical accessories since WWII. Their white moulded sockets are installed in millions of British homes.
Did you know? Originally a mail-order screws company called "Woodscrew Supply Company". Now the UK's largest multi-channel trade supplier with 870+ stores and same-day Click & Collect.
Did you know? Owned by Travis Perkins Group, Toolstation grew from a single store to 580+ branches in just 20 years — opening a new store almost every week.
Did you know? ITS (Industrial Tool Supplies) is one of the UK's largest independent tool retailers, known for competitive pricing and fast delivery across their 30+ trade counters.
Did you know? Named after founders Richard Block and David Quayle. B&Q opened the UK's first warehouse-style DIY store in 1980, changing how Britons shop for home improvement.
Did you know? A fast-growing online-only tool retailer specialising in premium brands like Milwaukee, Makita, and DeWalt with competitive pricing and expert product knowledge.
Did you know? Started as a small family business, Power Tool Mate has become one of the UK's most trusted online power tool specialists with over 100,000 satisfied customers.
Did you know? Tools4Trade is known for their detailed product videos and expert reviews, helping tradespeople make informed buying decisions before purchasing.
Did you know? Famous for their massive 25,000 sq ft flagship store in Devon — a destination for woodworkers worldwide. They manufacture their own brand of lathes and machinery.
Did you know? SGS specialises in air compressors, generators, and workshop equipment. They design and manufacture many products under their own brand name.
Did you know? Toolden has rapidly grown into a go-to online store for tradespeople, known for their clean website design, fast shipping, and excellent customer service.
Did you know? City Electrical Factors (CEF) is the UK's largest electrical wholesaler with over 450 trade counters. They hold £150M+ of stock for same-day availability.
Did you know? One of the oldest companies in the UK, Travis Perkins traces its origins to 1797. The group also owns Toolstation, Wickes, and several other major trade brands.
Did you know? Power Tool World is a family-run business that has grown into one of the North East's largest power tool retailers with a massive online catalogue.
Compare 3 prices for Sealey BT91/7PF Polarity Free Battery Drop Tester — from £56.95
to £66.49 across 3 UK sellers including
My Tool Shed, Tooled Up, UK Planet Tools.
Save up to £9.54 (14%).
The Sealey BT91/7PF is a polarity-free battery drop tester designed for quick and safe testing of 6V and 12V batteries. This American-style drop tester features polarity-protected cables that prevent damage from incorrect connections, making it a reliable diagnostic tool for workshops, garages and mobile mechanics. Built with internal switchgear, this battery tester applies load without sparking, enhancing safety during testing procedures. The unit applies load across battery cells and measures output on an integrated meter, providing accurate indication of battery voltage and identifying faulty or short-circuited cells. This makes it ideal for diagnosing battery condition before replacement, troubleshooting electrical issues in vehicles, and routine maintenance checks. The polarity-free design eliminates the risk of damaging the tester through reverse connections, offering peace of mind during busy workshop operations where quick testing is essential. Features and Benefits: • Polarity-protected cables prevent damage from incorrect connections • Internal switchgear eliminates sparking during load application • Suitable for both 6V and 12V battery systems • Integrated meter displays accurate voltage readings • Identifies faulty or short-circuited cells quickly Specifications: Brand: Sealey
