This is it
"Comfort and spin and still durable I use it in the mains with 18 ga synth in the crosses and its the best setup Ive had in a while"
Tourna
BHBK7-17:SET
For the ultimate in spin, Tourna Big Hitter Black 7 17 brings bite to a new level. This German-engineered copolyester string is designed for medium power and impressive spin. During the manufacturing process, this string is extruded through a special dye to create a sharp, seven sided string designed to grip and rip the ball. To improve playability, Big Hitter Black 7 was created with mid-range power, incredible precision, and comfort in mind. The co-polyester nature of the string allows it to remain durable while maintaining flexibility for a softer feel than traditional poly strings. Our testers were obviously most impressed with the spin generation of the string and the power level helped to keep balls deep with greater spin to dictate play from the baseline.
Construction: Co-polyester Monofilament
Color: Black
Gauge: 1.25 mm (17G)
Length: 12.2 m (40 ft)
Check out some of our informational blog posts on strings:
Tourna String Comparison: Something "Unique" for Everyone
Tourna String Review: Black Zone - Black 7- Quasi Gut Armor
Need help selecting a string? Check out our Choosing The Right Tennis String guide for more assistance.
Any original shipping fees are none refundable.

| From | To | Standard Ground* | 2Day | Next Day | |
|---|---|---|---|---|---|
| $0.00 | $49.99 | = | $5.95 | $15.95 | $29.95 |
| $50.00 | $149.99 | = | Free | $15.95 | $34.95 |
| $150.00 | $199.99 | = | Free | $19.95 | $39.95 |
| $200.00 | $9,999.99 | = | Free | $19.95 | $39.95 |
| From | To | USPS Priority* | |
|---|---|---|---|
| $0.00 | $99.99 | = | $19.95 |
| $100.00 | $199.99 | = | $39.95 |
| $200.00 | $9,999.99 | = | $49.95 |
Orders being shipped outside of the Contiguous US or APO addresses will ship by means of the United States Postal Service (USPS) and in some cases FedEx.
**Shipping via USPS Priority provides minimal tracking information and normally delivers within 5-7 business days.
*** Any shipping promotions offered by Tennis Express DOES NOT apply to shipments outside of the contiguous 48 states.
**** Excludes tennis balls, court equipment, stringing machines, ball machines and all oversized items.
At this time, Tennis Express only ships to the United States and all US Territories including Puerto Rico, US Virgin Islands, Guam and military bases. Due to manufacturer restrictions, we are unable to ship to countries outside of the United States.
Return Policy
Tennis Express believes in providing our customers with the best selection of tennis products and innovative game improvement gear. If the products are not to your liking, please take comfort in knowing you can return or exchange unused products within 30 days of the delivery date. Used or worn product is ineligible for a Refund. However, Tennis Express may issue a partial store credit for product returned in a used or worn condition. Credit is at the discretion of Tennis Express based on the amount of wear and use on the product. Store credits expire after 90 days.
How to Return
Submit a return request by visiting Return Portal.
1. Log in with your order number and email.
2. If your order has more than one item, select the items that you want to return.
3. Select the item condition and reason for return. Optionally add any comments.
4. Save and continue to return options.
Once your return request is approved, you'll receive an email with a label or QR code for your FedEx return label and shipping instructions. After the product is returned, you receive a refund.
To qualify for a FREE prepaid FedEx Ground return label:
* Your order must be over $50 (before tax and any shipping fees).
* After your return, the value of what you keep must still be over $50 (before tax and any shipping fees).
* Limit 1 free return label per order.
* Valid only for the continental United States.
Example: You place a $75 order and return a $30 item. Your remaining total is $45, which is under $50, so this order does NOT qualify for free return shipping.
If your order does not qualify for free return shipping, you can still use our return portal for a flat $6.95 fee, which will be deducted from your refund. Otherwise, you're responsible for shipping items back to us, so please hold onto your tracking information.
Please note:
* If you use one of our prepaid labels, you may drop the shipment off at any authorized FedEx or USPS Service Station.
* Refunds will be processed within 3-5 business days from the day we receive the return.
* Any original shipping fees are non-refundable.
* Any store credit issued will expire within 90 days.
QUESTIONS: If you have any questions about our return process, please contact us before shipping back your return: [email protected]
Apparel Returns and Exchanges
* Apparel must be unworn, unwashed, and unused with original tags attached.
* For safety concerns, we cannot accept used or washed clothing.
* Accessories must be unworn, unwashed, and unused with original tags attached.
* Apparel items carry NO warranty from the manufacturer.
Shoe Returns and Exchanges
* Shoes must be in NEW and unworn condition with original product packaging.
* DO NOT use the original shoe box as the outer shipping box. This will ruin the product.
* Accessories must be unworn, unwashed, and unused with original tags attached.
* For shoe outsole warranty claims, please visit our Shoe Warranty page.
Final Sale Notice: All Clearance Shoes and Apparel are Final Sale and not eligible for returns or exchanges.
Racquet and Paddle Returns and Exchanges
* Racquets or Paddles must be in NEW and unused condition with original plastic covering the handle intact.
* Make sure any racquets or paddles are protected to safely endure shipment.
* For racquets strung at Tennis Express, the cost of the string will not be refunded.
* All sales are final on the purchase of used racquets.
* For racquet warranty claims, please visit our Racquet Warranty webpage.
Drop Ship Returns
* Items shipped directly from the manufacturer must be returned to the manufacturer within 30 days of the original delivery date.
* You must request a Return Authorization (RA) from Tennis Express prior to shipping. Please email [email protected] with your return request.
* Drop shipped items must be in new and unused condition with original product packaging.
* Any restocking fees or return shipping costs will be paid for by the customer.
Damages and Issues
Please inspect your order upon reception and contact us immediately if the item is defective or damaged, or if you receive the wrong item, so that we can evaluate the issue and make it right.
Unfortunately, we cannot accept returns on gift cards.
Last Updated 05/07/26
Overall rating: 4.818182 / 5 from 11 reviews.
Review topics: ["power","balls","string","spin"].
"Comfort and spin and still durable I use it in the mains with 18 ga synth in the crosses and its the best setup Ive had in a while"
"Since switching to this string my forehand stays in play more and I have been able to generate more spin with less effort. I am a 3. 0 tennis player who took up the sport at 67. I wanted a string that is easy on my arm, elbow and shoulder. This is it for me."
"I am not a big topspin hitter but the Black 7 allows me to produce a lot of topspin. Many of my shots are often called out by my opponents before the ball hits and then the ball drops in and the call changes. It is amazing. Offensive top spin lobs are one of my favorite shots and I can paint the line regularly and then the ball jumps over the head of my opponent. Love the string. I work in a tennis shop and could get my string at discount but we dont currently carry this string and I love it so much that I order it. If you are looking for extra spin give this string a shot. I have a Wilson Steam 105 s and use the Black 7 17 gauge at 61 lbs. Havet broken a string yet so durability is a plus."
"I love it!!!!!! Will be ordering more!!!!"
"I switched to this string after using Babolat Hurricane tour for years, but found this string a worthy replacement without the big price. Nice touch, and enough power to generate spin in a hybrid combo with Prince synthetic gut."
"I strung a full bed 5# under. It was stiff/unresponsive for the first 2-3hrs. The spin was substantial at first but has gone down some. The power is very good. Ive had them in for two months. I play 3 times a week and the strings have minimal notching. They never move around, never. Worth a try for the price."
"This is a great soft poly string. I play with it in a Volkl 8 315g @ 57lbs prestretched and find that set up to be just about perfect for me. Easy to hit a deep, heavy ball with good control. Tension maintenance is very good for a soft poly. Performance doesnt seem to vary much as it loses tension either. Good option for those with mild elbow problems who want poly performance."
"Spectacular spin! Especially when strung under 50 pounds. It doesnt have a lot of power, so I feel free to take big swings. The feel is great; very solid and crisp."
"I cant say enough about this string. From the very first ball I hit while I was warming up to the last one 3 sets later, the ball went precisely where I wanted it to. Incredible, Ive played with many different strings and racquets in the last 56 highly competitive years and by far these strings have made the most difference. For the first time it feels like I dont have a tennis racquet in my hand, but a precision tool. No loss of power and more control, what a combination. What else could you ask for. Im using the 17ga with the midrange tension 55# in my Prince Rebel racquet. Simply amazing."
"For years, I had played with the Babolat Pro Huricane strings. The Tourna Black 7 delivers the equivalent performance, with more feels, and less $$$."