We’re using DTM connectors for a new sports car project and we have to keep costs in check. So let’s talk suppliers.
RS Components & Farnell
First up is RS Components & Farnell (Digikey & Mouser are a little better) but their prices are crazy! A single #20 gauge DTM socket costs 71p, and even if you buy 100, you can only get it down to 68p. Another issue is that when trying to find complementary parts on the website, you need the housing, lock, contacts and then the parts for the mating half, this is rarely a quick and easy process. A kit of parts for a DTM 6 way sockets is £12.67+VAT and delivery, Wow!
AliExpress
Then there’s AliExpress. They sell non genuine parts and kits at affordable prices, but the quality can be marginal at best. The housings are typically acceptable for less critical projects but the seals? Not great, I have found them too often oversized or swell, stopping the mating halves easily clicking together. Locks can be a tight fit but are generally OK. However the real issues comes with the contacts, these are almost always stainless steel and they don’t crimp well at all.
A genuine DTM #20 contact’s body is made from a nickel plated copper alloy. When crimped the indent dies deform the wire bucket, leaving a consistent crimp around the strands of wire. However, if you use stainless steel contacts, the eight point indent crimp tool doesn’t bring the sides of the bucket down, it actually punches through the sides. The result is a really poor crimp, especially on the smaller gauges. We have found that the quality of the Crimp has poor wire retention and suffers from high resistance issues when passing working current.
Frankly, stainless steel contacts do not crimp to a standard that even a hobby racer should accept. Let’s not save pence when it’s going to cost us pounds in fault-finding and rectification. At some point these contacts are almost certainly going to cause you issues. So we advise anyone, even if you’re using the low cost housings to avoid these stainless steel contacts.
Formed contacts
Another side note. you can get formed contacts for DTMs, made from pressed sheet. These can be easier to crimp for some hobbists but the reason we (in motorsport) still widely use DTM connectors is for the bullet proof reliability, current capacity and quality of the ‘Turned’ / Solid / Barrel style contacts. Always use this type and avoid the formed contacts whenever possible, if you need affordable crimp tools just get in touch with www.WireTrain.uk we have a source of dedicated DTM and DT crimp tools that produce a very capable crimp and are very affordable at under £40.
Good news!
Now, the good news on costs. We use two excellent UK suppliers: Retrofit Parts and Three Way Components. Postage is quick and low cost for even smaller orders.
3 Way Components » Leading Online Automotive Retailer
A great advantage of these suppliers is that they supply pre-kitted connectors, all the parts you need in one low cost kit price. Housing, Lock and Contacts.
They also have many of the harder to find variants, such as the alternate keyway black versions, which are handy since you can have two connectors on your loom, same pin-count and gender but they can’t be mismatched due to the different mechanical keyways of the black and grey housings.
E003 and E007 variants
Commonly requested are the E003 and E007 variants of DTM housings which allow easy booting. The E003 variant is for housings taking pins and have a bonded on flange that allows a heatshrink boot to grip the back of the body, the E007 variants are for housings taking sockets and extend the back of the housing with a ribbed section for boot bonding.
One thing I would note, if you don’t need that extended housing for booting, the extended section does make it slightly harder to hand-insert contacts into the connectors. So if you don’t need it, you may find it easier and cheaper to purchase the standard housings.
Quick overview of the savings
RS Components
#20 gauge sockets £0.71
#20 gauge Pins £0.43
DTM 6 Way with Sockets Kit £12.67
DTM 3 Way with Pins Kit £7.14
RetroFitParts
#20 gauge sockets £0.41
#20 gauge Pins £0.41
DTM 6 Way with Sockets Kit £4.80
DTM 3 Way with Pins Kit £3.00
3 Way Components
3 Way Components » Leading Online Automotive Retailer
#20 gauge sockets £0.52 or £0.33 for 100+
#20 gauge Pins £0.24 or £0.15 for 100+
DTM 6 Way with Sockets Kit £4.86
DTM 3 Way with Pins Kit £2.23
We use both of these suppliers and have found them to be excellent. DTM connectors are still great for projects and racing. Why settle for overpriced, or low-quality parts when these guys provide the geniune parts at great prices!
That’s it for now, talk soon!
John @ WireTrain.
P.S. a quick reminder we are running out WireTrain Pro Wiring Workshop for Individuals on 4th and 5th of August 2026. Get in touch if your interested.
ooh, lastly…love a DTM style contact but want 41 pins in your housings, or looking for a bulkhead connector for your engine bay? Take a look at the HDP20 series!