what does the number stand-for for the countersink cutter? sometime is #40, #21, sometime is 1/4", I need 1/8" or 5/32", do you have?

The number is standard drill size. #40 being slightly larger than 3/32" and #30 slightly larger than 1/8". A quick google will give you a conversion chart. They do also sell them in standard sizes like 3/32 or 1/4, but you may have to contact ATS directly.

Although this seems to be used for rivets on aircraft, can it also be used on solid aluminum and steel millwork projects for flat head machine screws?

Hello, Unfortunately this item will not work for the purpose you are proposing. These pilot cutters are 100 degree 3 flute cutting edge and I believe if you are using AN screws they will require a 82 degree cutter which we do not sell.

What is the Thread size of the cutter's shank? (IE 1/4-28 ?)

It looks like 1/4" 28. I don't have any fine thread nuts around. It catches the first thread on 1/4 20 but won't go any further.

Is it 60 degrees or, like most countersinks, 80 degrees? They don't say in the description.

100 degree counter sinks -- for standard aviation rivets AD426-xxxx

Fully operational. Shipping worldwide, on schedule.Customs & duties included in the price

Help Track order

Account Cart

Fully operational. Shipping worldwide, on schedule.Customs & duties included in the price

Help Track order

Account Cart

Aircraft Tool Supply Countersink Kit W/Pilot Cutter by Aircraft Tool Supply

Product ID: 347818085

Details

Brand
Aircraft Tool
Cutting angle string
9E+1 Degrees
Finish type
Uncoated
Material
metal
Shank type
Straight

🎯Pilot cutter ensures pinpoint accuracy

⚙️2-flute spiral for smooth chip removal

🛠️Stainless steel for corrosion resistance

S$187

Duties & taxes included

In stock

Sold byAmazon SINGAPOREDelivered byDesertcartCustomer service byDesertcartReturns14 days · 30 with PRO

Buyer Protection · Full refund if your order doesn't arrive as described.

Desertcart purchases this item on your behalf and handles shipping, customs, and support to SINGAPORE.

Secure transaction

ProDesertcart PRO

Fast, free shipping, member pricing & priority support.

Join PRO →

Description

🎯 Drill with precision, finish with pride!

BUILT TO LAST - Durable stainless steel construction resists corrosion and wear
METAL MASTERY - Optimized for metal surfaces, making it your go-to for versatile projects
PINPOINT ACCURACY - Included pilot cutter guarantees exact starting points for perfect countersinks
PRECISION PERFECTED - Professional-grade countersink for flawless, clean holes every time
EFFORTLESS EFFICIENCY - 2-flute spiral design minimizes binding and speeds up your workflow

The Aircraft Tool Supply Countersink Kit features a professional-grade, 2-flute spiral bit made from corrosion-resistant stainless steel. It includes a pilot cutter for precise hole starting points, designed specifically for clean, accurate countersinking in metal surfaces. This durable, efficient tool is essential for any serious DIYer or professional aiming for flawless results.

Specifications

ASIN	B005VR821G
Best Sellers Rank	919,494 in DIY & Tools ( See Top 100 in DIY & Tools ) 836 in Countersink Bits
Brand	Aircraft Tool Supply
Cutting Angle String	9E+1 Degrees
Finish Types	Uncoated
Item Dimensions	18.3 x 9 x 2.9 centimetres
Item Weight	1 Pounds
Manufacturer	Aircraft Tool Supply
Manufacturer Part Number	133KIT
Material	metal
Minimum Bore Diameter	0.06 Inches
Model Number	Aircraft Tool Supply [SOMETHING]
Number of Flutes	2
Number of Packs	1
Number of Pieces	137
Point Style	Taper Point
Set Name	Countersink Kit
Shank Type	Straight
Surface Recommendation	Metal
Tool Flute Type	Spiral
Unit Count	1.0 count

Common Questions

Are the products genuine and authentic?+

Yes, all products are sourced directly from authorized retailers in the US, UK, UAE and India. We maintain strict quality control processes and verify each product before shipping. All items come with applicable manufacturer warranties and are covered by our standard return policy.

How long does delivery take and is it reliable?+

Delivery times vary by destination country, typically ranging from 3-9 business days. Each order is fully trackable through our system. We handle all customs clearance and use reliable courier partners for last-mile delivery. You'll receive regular updates about your order status via email and our app.

What is Desertcart? Is it safe to order from?+

Desertcart is an international e-commerce platform operating since 2014. We securely process thousands of orders globally each day. Every product goes through our quality verification process before delivery, and we provide end-to-end order tracking, 24/7 customer support, and a comprehensive returns policy to ensure a safe shopping experience.

How is product pricing calculated?+

Our prices include the product cost, international shipping, import duties, customs clearance, and local delivery charges. We handle all customs and import procedures, ensuring there are no hidden fees upon delivery. PRO members receive additional benefits including free shipping.

Trustpilot

TrustScore 4.5 | 7,300+ reviews

Neha S.

Excellent communication throughout the order process. Product is perfect.

2 weeks ago

Vikram D.

The MOLLE sheath is of exceptional quality. Very happy with my purchase.

2 weeks ago

View all Trustpilot reviews

Shop Global, Save with Desertcart

Value for Money

Competitive prices on a vast range of products

Shop Globally

Serving millions of shoppers across more than 100 countries

Enhanced Protection

Trusted payment options loved by worldwide shoppers

Customer Assurance

Trusted payment options loved by worldwide shoppers.

Desertcart App

Shop on the go, anytime, anywhere.

S$187

Duties & taxes included

In stock

Sold byAmazon SINGAPOREDelivered byDesertcartCustomer service byDesertcartReturns14 days · 30 with PRO

Buyer Protection · Full refund if your order doesn't arrive as described.

Desertcart purchases this item on your behalf and handles shipping, customs, and support to SINGAPORE.

Secure transaction

ProDesertcart PRO

Fast, free shipping, member pricing & priority support.

Join PRO →

Trustpilot

TrustScore 4.5 | 7,300+ reviews

Anjali K.

The product quality is outstanding. Exactly what I needed for my work.

1 month ago

Ravi S.

I loved the variety of products available. Will definitely shop again.

2 months ago

View all Trustpilot reviews